On selling a chair for ₹ 720 a dealer loses 4 for how much should he sell it to gain 12

  • Textbook Solutions
  • Class 7
  • Math
  • profit and loss

Rs Aggarwal 2018 Solutions for Class 7 Math Chapter 11 Profit And Loss are provided here with simple step-by-step explanations. These solutions for Profit And Loss are extremely popular among Class 7 students for Math Profit And Loss Solutions come handy for quickly completing your homework and preparing for exams. All questions and answers from the Rs Aggarwal 2018 Book of Class 7 Math Chapter 11 are provided here for you for free. You will also love the ad-free experience on Meritnation’s Rs Aggarwal 2018 Solutions. All Rs Aggarwal 2018 Solutions for class Class 7 Math are prepared by experts and are 100% accurate.

Page No 157:

Question 1:

Find the SP when:

(i) CP = Rs 950, gain = 6%
(ii) CP = Rs 9600, gain = 1623%
(iii) CP = Rs 1540, loss = 4%
(iv) CP = Rs 8640, loss = 1212%

Answer:

(i) CP = Rs. 950
Gain = 6%

    SP ={(100 + Gain%)100× CP }  = {(100 + 6)100× 950} = 106100× 950 = 100700 100 = Rs. 1007

   (ii) CP = Rs. 9600
Gain = 1623% = 50 3%

            SP={ (100 + Gain%)100× CP} = {(100 + 503)100× 9600} = 350300 ×9600 = 33603 = Rs . 11200

  (iii) CP = Rs. 1540
Loss = 4%

                SP={(100 - Loss%)100× CP}  = {(100 - 4)100× 1540} = 96100× 1540 = 147840100  = Rs. 1478.40

(iv) CP = Rs. 8640  
Loss = 1212% = 252%

        SP={(100 - Loss%)100× CP} = {(100 - 252 )100× 8640} = 175200× 8640 = 1512000200 = Rs. 7560

Page No 157:

Question 2:

Find the gain or loss per cent when:

(i) CP = Rs 2400 and SP = Rs 2592
(ii) CP = Rs 1650 and SP = Rs 1452
(iii) CP = Rs 12000 and SP = Rs 12800
(iv) CP = Rs 1800 and SP = Rs 1611

Answer:

(i) CP = Rs. 2400  
SP = Rs. 2592
    Gain = SP - CP = Rs. ( 2592 - 2400) = Rs. 192

      Gain%  = GainCP × 100 = 1922400× 100 = 8

(ii) CP = Rs. 1650  
SP = Rs. 1452
    Loss = CP - SP = ( 1650 - 1452) = Rs. 198

         Loss%  = LossCP × 100 =1981650 × 100  = 12

(iii) CP = Rs. 12000   and   SP = Rs. 12800
    Gain = SP - CP = ( 12800 - 12000) = Rs. 800

         Gain% = GainCP × 100 = 80012000× 100 = 6.66

(iv) CP = Rs. 1800  
SP = Rs. 1611
     Loss = CP - SP = ( 1800 - 1611) = Rs. 189

         Loss% = Loss CP × 100 =1891800 × 100 = 10.5

Page No 157:

Question 3:

Find the CP when:

(i) SP = Rs 924, gain = 10%
(ii) SP = Rs 1755, gain = 1212%
(iii) SP = Rs 8510, loss = 8%
(iv) SP = Rs 5600, loss = 623%

Answer:

(i) SP = Rs. 924  
Gain = 10%

       CP ={ 100(100 + Gain%)× SP} 

={100(100 + 10) × 924} = 92400110 = Rs. 840

(ii) SP = Rs. 1755  
Gain = 1212% = 252%

       CP = {100(100 + Gain%)× SP} ={100(100  + 252)× 1755} =  {200225× 1755} = 351000225  = Rs. 1560

                                  (iii) SP = Rs. 8510  
Loss = 8%

              CP = {100(100  - Loss%)× SP} = {100(100 - 8 )× 8510} =  85100092= Rs. 9250

  (iv) SP = Rs. 5600  
Loss = 623% = 203%

           CP = {100(100 - Loss%)× SP} = {100(100 -  203)×5600} = {300280× 5600} = 16800028 = Rs.  6000

Page No 157:

Question 4:

Sudhir bought an almirah for Rs 13600 and spent Rs 400 on its transportation. He sold it for Rs 16800. Find his gain per cent.

Answer:

Cost price of an almirah = Rs. 13600
Transportation cost = Rs. 400
Total cost price = Rs. (13600 + 400) = Rs. 14000
Selling price = Rs. 16800
Now, SP > CP
Gain = SP - CP = ( 16800 - 14000) = Rs. 2800

Gain% = GainCP× 100 %

= 280014000× 100%

=2800140% = 20%

Page No 157:

Question 5:

Ravi purchased an old house for Rs 765000 and spent Rs 115000 on its repairs. Then, he sold it at a gain of 5%. How much did he get?

Answer:

Cost price of the house = Rs. 765000
Cost  of repairing the house = Rs. 115000
Total Cost price = (765000 + 115000) = Rs. 880000
Ravi sold it at a gain of 5%.

 SP= {(100 + gain %)100 × CP}= {(100 + 5)100× 880000} = 105100× 880000  = Rs. 924000

 He gets Rs. 924000.

Page No 157:

Question 6:

A vendor busy lemons at Rs 25 per dozen and sells them at the rate of 5 for Rs 12. Find his gain or loss per cent.

Answer:

CP of 12 lemons (dozen) = Rs. 25
CP of one lemon = Rs. 2512

CP of five lemons = 5 ​× 2512 = 12512 = Rs. 10.42

SP of five lemons = Rs. 12            (given)

Gain = SP - CP = ( 12 - 10.42 ) = Rs 1.58

Gain% =GainCP× 100%

=1.5810.42 × 100  %

= 15.2%

Page No 157:

Question 7:

The selling price of 12 pens is equal to the cost price of 15 pens. Find the gain per cent.

Answer:

Let the cost price of the pen be Re 1.
Cost price of 12 pens = Rs 12
SP of 12 pens = CP of 15 pens = Rs 15
Gain = SP - CP = Rs (15 - 12) = Rs 3

Gain%  = GainCP× 100 %

=312× 100 %= 25%

Gain% = 25%

Page No 157:

Question 8:

The selling price of 16 spoons is equal to the cost price of 15 spoons. Find the loss per cent.

Answer:

Let the cost price of one spoon be Re 1.
CP of 16 spoons = Rs 16
SP of 16 spoons = CP of 15 spoons = Rs 15
Loss = CP - SP = (16 - 15) = Re 1

Loss% = Loss CP× 100% = 116× 100 %=6.25%

Loss% = 6.25%

Page No 157:

Question 9:

Manoj purchased a video for Rs 12000. He sold it to Rahul at a gain of 10%. If Rahul sells it to Rakesh at a loss of 5%, what did Rakesh pay for it?

Answer:

Cost price of a video = Rs. 12000
SP of a video at a gain of 10% ={(100 + Gain%)100× CP}

 ={(100 + 10)100× 12000} = {110100× 12000} =  Rs.13200

So, Rahul purchased at a cost price of Rs. 13200.

Rahul sells it at a loss of 5%.

SP of a video at loss of 5% = {(100 - Loss%)100× CP} 

= {(100 - 5)100× 13200} = 95100× 13200 = Rs. 12540

∴ Rakesh pays = Rs. 12540

Page No 157:

Question 10:

On selling a sofa-set for Rs 21600, a dealer gains 8%. For how much did he purchase it?

Answer:

SP of the sofa set = Rs. 21600
Gain% = 8

 CP of the sofa set={100( 100 + Gain%)×SP} = {100(100 + 8) × 21600} = 2160000108 = Rs. 20000

He purchased it at the cost of Rs. 20000.

Page No 157:

Question 11:

On selling a watch for Rs 11400, a shopkeeper loss 5%. For how much did the purchase it?

Answer:

SP of the watch = Rs 11400
Loss% = 5

CP = {100(100 - Loss%)× SP} 

={100(100 - 5)× 11400} = 1140095 = Rs. 12000

 He purchased it at the cost of Rs. 12000.

Page No 157:

Question 12:

On selling a calculator for Rs 1325, a man gains 6%. For how much should he sell it to gain 12%?

Answer:

SP of the calculator = Rs. 1325
Gain % = 6

CP of the calculator = {100(100 + Gain% )× SP} 

={100(100 + 6)×1325} = 132500106 =  Rs. 1250

               SP of the calculator= {(100 + Gain%)100× CP}  = {(100 + 12)100× 1250} = 140000100 = Rs.1400

Page No 157:

Question 13:

On selling a computer for Rs 24480, a dealer loses 4%. For how much should he sell it to gain 4%?

Answer:

SP of a computer = Rs. 24480
Loss% = 4

   CP of the computer={100( 100 - Loss%)× SP} = {100(100 - 4)× 24480} = 2448000 96= Rs. 25500

In order to gain 4%:
   SP of the computer={(100 + Gain%)100 × CP} = {(100 + 4)100× 25500} = {104100× 25500}  = 2652000100 = Rs. 26520

Page No 157:

Question 14:

A tricycle is sold at a gain of 15%. Had it been sold for Rs 108 more, the profit would have been 20%. Find its cost price.

Answer:

Let the CP of the tricycle be Rs. x

SP at 15% gain = {(100 + Gain%)100× CP} 
={(100 + 15) 100× x} = 115100x

=Rs. 2320x

SP at 20% gain = x ×  120100 = Rs. 65x

65x-2320x=108⇒24x-23 x20=108⇒x20=108⇒x=2160

Hence, the cost price of the tricycle is Rs. 2160

Page No 157:

Question 15:

Sandeep sold a television at a loss of 8%. If he had sold it for Rs 3360 more, he would have gained 6%. For how much did Sandeep buy it?

Answer:

Let CP of  a television be Rs x.
SP at 8% loss =  (100 - 8)100× x = Rs. 92100 x
                     100
SP at 6% gain =     (100 + 6)100× x = Rs. 106100x

      106100x - 92100x = 3360

                         ⇒14100x = 3360

                                                                                                   ⇒         x =  33600014 = 24000

∴ CP = Rs. 24000
Sandeep bought it at the cost of Rs. 24000.

Page No 157:

Question 16:

Pankaj sells two cycles for Rs 2376 each. On one he gains 10% and on the other he loss 10%. Find his gain or loss per cent.

Answer:

SP of each cycle = Rs. 2376
He gains 10% in one cycle.
CP = {100(100 + Gain%)× SP} 
 ={100(100 + 10) ×  2376} = 100110× 2376 = Rs. 2160

He looses 10% in the second cycle.
CP = 100(100 -  Loss%) × SP

=100(100 - 10)× 2376= 10090× 2376  = 237609 = Rs. 2640

Total CP = Rs. ( 2160 + 2640 ) = Rs . 4800                                                                            
Total SP =    Rs. ( 2376 +  2376 ) = Rs. 4752                                                                         
 Loss = CP - SP = Rs . ( 4800 - 4752 ) = Rs. 48
    Loss%  = LossCP× 100 %
=484800 × 100% = 1%

Page No 157:

Question 17:

On selling an exhaust fan for Rs 7350, a man gains 1 6 of its cost price. Find the cost price of the fan.

Answer:

Let the CP of the exhaust fan be Rs. x.
Gain = Rs. x6

​SP =  Rs ( x +  x6)

      SP = Rs. 7350

∴     x + x6 = 7350
 ⇒    76x = 7350
⇒        x = 7350 × 67 = 441007 =6300
CP of the fan = Rs. 6300

Page No 157:

Question 18:

Mohit sold a watch to Karim at a gain of 10% and Karim sold it to Rahim at a gain of 4%. If Rahim pays Rs 14300 for it, for how much did Mohit purchase it?

Answer:

Mohit sold a watch to Karim at Rs. x.
Mohit sold it at a gain of 10%.
SP of the watch = 110% of x
                  =  (x + 110100) = Rs. 1120x                                                                        
Karim sold it to Rahim at a gain of 4%.
SP of the watch = 104% of 1110x =  (104100 × 1110x)  = Rs. (2625× 1110x)

                                                                                                     But, Rahim pays Rs. 14300.
∴ 2625× 1110x = 14300

⇒x = 14300 ×  25 × 1026 × 11 =3575000286 =12500

Mohit purchased it at Rs. 25000.

Page No 157:

Question 19:

If the manufacturer gains 10%, the wholesale dealer 15%, and the retailer 25% then what is the production cost of a washing machine whose retail price is Rs 37950?

Answer:

Let the production cost of a washing machine be Rs. x.
Profit of the manufacturer  = 10%
SP of the manufacturer = 110% of x
                                    =  (x + 110100) = 110100x = Rs. 1110                                                             
Profit of the wholesale dealer = 15%
SP of the wholesale dealer =   115% of Rs 1110x                                           
                                        = Rs (1110x × 115100) = Rs ( 1110x × 2320)

                                            Profit of the retailer = 25%
SP of the retailer = 125% of Rs  (1110x × 2320)

                                                     = Rs. ( 1110 x × 2320×125100) = Rs. (1110x × 2320× 54)

                                 Given:
Retail price = Rs. 37950
∴ (1110x × 2320 × 54) = 37950

                                                                                                                               ⇒x =  37950 × 10 × 20 × 411 × 23 × 5 
=> x= 303600001265 =  24000

                                       ∴ Production cost of a washing machine = Rs. 24000

Page No 157:

Question 20:

Mr Mehta purchased a video for Rs 20000 and a television for Rs 30000. On the video he lost 5% and on the television he gained 8%. Find his total gain or loss per cent.

Answer:

Mr. Mehta purchased a video at the cost of Rs. 20000.
Mr. Mehta purchased a television at the cost of Rs. 30000.
Total cost = Rs. (20000 + 30000) = Rs. 50000

He lost 5% on the video.

SP= (100-Loss%)100×CP= 100-5100×20000=95100×20000=Rs. 19000

                                                  He gained 8% on the television.

SP= (100+Gain%)100×CP=100+8100×30000=108100×30000 =Rs. 32400

                                                                                  Total SP =  Rs.  ( 190000 + 32400 ) = Rs. 51400

                                                                                 Total CP = Rs. 50000
Total Gain = SP - CP = Rs. ( 51400 - 50000 ) = Rs. 1400                                                     
Gain% = GainCP× 100 %=  140050000 × 100 % = 2.8%

Page No 158:

Question 21:

By selling 36 oranges, a vendor suffers a loss equal to the selling price of 4 oranges. Find his loss per cent.

Answer:

Let the CP of 1 orange be Rs. x.
∴ CP of 36 oranges = Rs. 36x
Let SP of orange be Rs. y.
∴ SP of 36 oranges = Rs. 36y

​Loss = SP of 4 oranges = 4y      (given)

We know:
Loss = CP - SP 
         ⇒            4y = 36x - 36 y
        ⇒            4y + 36y = 36x  
        ⇒                      40y  = 36x
        ⇒                         10y = 9x
​        ⇒                             y = 910x

                                Loss% = LossCP×100 %

=4y36x× 100 %

=4 × 9x36x× 10×  100% = 10%

   ​Loss% = 10%

Page No 158:

Question 22:

By selling 8 dozen pencils, a shopkeeper gains the selling price of one dozen pencils. Find his gain per cent.

Answer:

Let the CP of one pencil be Rs. x.
Therefore, the CP of 96 pencils will be Rs. 96x.
Let SP of one pencil be Rs. y.
​∴ SP of 96 pencils = Rs. 96y
Gain= SP of one dozen pencil = Rs.12y           (given)

Gain = SP - CP

       ⇒12y=96y-96x⇒96x= 96y-12y⇒96x=84y⇒x=84y96

                                Gain% = GainCP×100 %=12y96x×100%=12 y×9696×84y×100%=14.28%

Page No 158:

Question 1:

Mark (✓) against the correct answer
A man buys a book for Rs 80 and sells it for Rs 100. His gain % is

(a) 20%
(b) 25%
(c) 120%
(d) 125%

Answer:

(b) 25%

CP of the book = Rs. 80
SP of the book = Rs. 100
Gain = SP - CP = Rs. (100 - 80) = Rs. 20
Gain% = GainCP× 100 % = 2080× 100 %= 25%

Page No 158:

Question 2:

Mark (✓) against the correct answer
A football is bought for Rs 120 and sold for Rs 105. The loss % is

(a) 1212%
(b) 1427%
(c) 1623%
(d) 1313%

Answer:

(a) 1212%

CP of a football = Rs. 120
SP of a football = Rs. 105

CP>SP
∴ Loss = CP - SP = Rs. ( 120 - 105 ) = Rs. 15
Loss% = LossCP × 100 %= 15120× 100 %= 252 %= 1212%

Page No 158:

Question 3:

Mark (✓) against the correct answer
On selling a bat for Rs 100, a man gains Rs 20. His gain % is

(a) 20%
(b) 25%
(c) 18%
(d) 22%

Answer:

(b) 25%

SP of the bat = Rs. 100
Gain = Rs. 20

 Gain = SP - CP 
     ⇒    20  = 100 - CP
    ⇒   CP = 100 - 20 = Rs. 80

Gain% = GainCP× 100 %=2080× 100% =  25%

Page No 158:

Question 4:

Mark (✓) against the correct answer
On selling a racket for Rs 198, a shopkeeper gains 10%. The cost price of the racket is

(a) Rs 180
(b) Rs 178.20
(c) Rs 217.80
(d) Rs 212.50

Answer:

(a) Rs. 180

SP of the racket = Rs. 198
Gain% = 10

   CP of the racket={100(100 + Gain%)× 100} = {100 (100 + 10)× 198} =100110× 198 = Rs. 180

Page No 158:

Question 5:

Mark (✓) against the correct answer
On selling a jug for Rs 144, a man loses 17 of his outlay. If it is sold for Rs 189, what is the gain%?

(a) 50%
(b) 25%
(c) 30%
(d) 12%

Answer:

Let the cost price be Rs. x.
 Loss = Rs. x7
∴  SP =   (x - x7) = Rs. 67x

Given:
SP = Rs. 144

∴  67x = 144 
⇒ x = 144 × 76 =Rs. 168

∴ CP = Rs. 168
SP = Rs. 144

New SP = Rs. 189
Gain = SP - CP = Rs. ( 189 - 168 ) = Rs. 21

                      Gain%  = GainCP× 100%= 21168× 100%=12.5%

The correct answer is 12.5%.
All the given options are wrong.

Page No 158:

Question 6:

Mark (✓) against the correct answer
On selling a pen for Rs 48, a shopkeeper loses 20%. In order to gain 20% what would be the selling price?

(a) Rs 52
(b) Rs 56
(c) Rs 68
(d) Rs 72

Answer:

(d) Rs. 72

SP of the pen = Rs. 48
Loses = 20%
Then , CP = {100(100 - Loss%)× SP} 
={100(100 - 20) × 48}= Rs. 60

In order to gain 20%:

SP = {(100 + Gain%)100× CP}  = {(100 + 20)100× 60} = 120100× 60 = Rs.  72

Page No 158:

Question 7:

Mark (✓) against the correct answer
If the cost price of 12 pencils is equal to the selling price of 15 pencils, then the loss% is

(a) 20%
(b) 25%
(c) 3%
(d) 1623%

Answer:

(a) 20%

Let the cost price of each pencil be Rs.1
Cost of 15 pencils = Rs 15
SP of 15 pencil = CP of 12 pencil = Rs 12
∴ CP = Rs 15
    SP = Rs 12

Loss = CP - SP =  Rs (15 -12) = Rs 3

Loss% = LossCP× 100 %= 315× 100%  = 300 15%= 20%

Page No 158:

Question 8:

Mark (✓) against the correct answer
If the cost price of 4 toffees be equal to the selling price of 3 toffees, then the gain% is

(a) 25%
(b) 30%
(c) 1623%
(d) 3313%

Answer:

(d) 3313%

Let the cost price of each toffee be Rs. 1
Cost price of three toffees = Rs 3
SP of three toffees = CP of four toffees =  Rs 4

CP = Rs 3  
SP = Rs 4

Gain = SP - CP = Rs ( 4 - 3 ) = Re 1
Ga in% = GainCP× 100% = 13× 100 %= 1003% =3313%

Page No 158:

Question 9:

Mark (✓) against the correct answer
On selling an article for Rs 144 a man loses 10%. At what price should he sell it to gain 10%?

(a) Rs 158.40
(b) Rs 172.80
(c) Rs 176
(d) Rs 192

Answer:

(c) Rs. 176

SP of an article = Rs. 144 
Loss% = 10
CP = {100(100 - Loss%)× SP}  = {100(100 - 10)× 144} = 10090× 144 = 14409= Rs. 160

In order to gain 10%:

S.P. = (100 + Gain%)100× CP=  (100 + 10)100× 160= 110100× 160= Rs. 176

Page No 159:

Question 10:

Mark (✓) against the correct answer
A vendor bought lemons at 6 for a rupee and sold them at 4 for a rupee. His gain % is

(a) 50%
(b) 40%
(c) 3313%
(d) 1623%

Answer:

(a) 50%

CP of six lemons = Re 1
CP of one lemon = Rs 16

CP of four lemon = Rs 46
SP of four lemon = Re 1

 Gain =  1 -  46 =26 = Rs 13
Gain%=GainCP× 100 =  32×3× 100 = 1002=50

Page No 159:

Question 11:

Mark (✓) against the correct answer
On selling a chair for Rs 720, a man gains 20%. The cost price of the chair is

(a) Rs 864
(b) Rs 576
(c) Rs 650
(d) Rs 600

Answer:

(d)Rs. 600

SP of the chair = Rs 720
Gain% = 20

C.P. = {100(100 + Profit  percentage)× S.P.} ={100120× 720} = 720012 = Rs.  600

Page No 159:

Question 12:

Mark (✓) against the correct answer
On selling a stool for Rs 630, a man loses 10%. The cost price of the stool is

(a) Rs 567
(b) Rs 693
(c) Rs 700
(d) Rs 730

Answer:

(c) Rs. 700

SP of a stool = Rs 630
Loss% = 10
CP = {100(100 - Loss%)× SP} ={100(100 - 10) × 630} = 10090×630 = Rs 700

Page No 160:

Question 1:

By selling a chair for Rs 1375 a man gains 10%. Find its cost price.

Answer:

SP of the chair = Rs 1375
Gain% = 10

 CP of the chair={100(100 + Gain%)× SP} 

={100(100 + 10)× 1375} =137500110 = Rs. 1250

Page No 160:

Question 2:

If the selling price of 10 pens is equal to the cost price of 14 pens, find gain per cent.

Answer:

Let the cost of each pen be Rs. 1
CP of 10 pens = Rs. 10
SP of 10 pens = CP of 14 pens = Rs. 14
Gain = SP - CP = 14-10= Rs. 4
Gain% = GainCP ×  100% = 410× 100%= 40%

Page No 160:

Question 3:

On selling a fan for Rs 2585 a man gains  110 of its cost price. Find the cost price of tha fan.

Answer:

Let the cost price of the fan be Rs. x.
Gain = Rs. x10
SP of the fan = ( x + x 10)= Rs. 1110x                                                                  
SP of the fan = Rs. 2585       
∴  1110x = 2585 
⇒ 11x = 25850 
⇒ x = 25850 11 = 2350

So, CP of the fan is Rs. 2350.

Page No 160:

Question 4:

A man buys lemons at 6 for Rs 10 and sells at 8 for Rs 15. Find his gain per cent.

Answer:

Cost price of six lemons = Rs. 10
Cost price of one lemon = Rs. 106
Cost price of eight lemons =  8 × 106 = Rs. 806 = Rs. 13.33                                         
Selling price of eight lemons = Rs. 15

  Gain = SP- CP=Rs. (15 - 13.33) = Rs.  1.67

                                                            Gain% = GainC.P.× 100  %
=1.6713.33× 100  %
=12.5%

Page No 160:

Question 5:

On selling a bat for Rs 486 a man loses 10%. Find the cost price of the bat.

Answer:

SP of the bat = Rs 486
Loss = 10%
CP of the bat = {100(100 - Loss%)× SP} 
={100 (100 - 10)× 486} =  4860090 = Rs 540

CP of the bat = Rs 540

Page No 160:

Question 6:

Mark (✓) against the correct answer
On selling a football for Rs 100, a man gains Rs 15. The cost price of the football is

(a) Rs 115
(b) Rs 85
(c) Rs 70
(d) Rs 130

Answer:

(b) Rs 85

SP of a football = Rs 100
Gain = Rs 15
Gain = SP - CP
        ⇒    15 = 100 - CP
       ⇒    CP = Rs (100 - 15)
       ⇒    CP= Rs 85

Page No 160:

Question 7:

Mark (✓) against the correct answer
A vendor buys lemons at Rs 25 per dozen and sells at 5 for Rs 12. His gain per cent is

(a) 14.5%
(b) 15%
(c) 15.2%
(d) 16%

Answer:

(c) 15.2%

Cost price of 12 bananas = Rs. 25
Cost price of one banana = Rs. 2512
  Cost price of five bananas=Rs. 5 × 25 12 = Rs. 12512 =Rs. 10.42

He sells five bananas at the cost (SP) of Rs. 12.
Gain = SP - CP

= =Rs. ( 12 - 10.42) = Rs. 1.58

 Gain% = GainCP× 100 % = 1.5810.4× 100 %= 15.2%

Page No 160:

Question 8:

Mark (✓) against the correct answer
On selling a jug for Rs 168, a man loses 17 of his outlay. The cost price of the jug is

(a) Rs 144
(b) Rs 192
(c) Rs 196
(d) none of these

Answer:

(c) Rs. 196

Let the cost price of the jug be Rs. x.
Loss = Rs. x7
SP of the jug = CP - Loss
=Rs. ( x - x7) = Rs. 6 7x

                                                                                     ​SP of the jug = Rs 168         (given)

∴   67x = 168 
⇒=168 × 76 ⇒x= 11766  ⇒x=196

    ∴ CP of the jug = Rs. 196

Page No 160:

Question 9:

Mark (✓) against the correct answer
If the cost price of 5 bananas be equal to the selling price of 3 bananas, then gain per cent is

(a) 3313%
(b) 15%
(c) 6623%
(d) 40%

Answer:

(c) 6623%

Let the cost price of each banana be Re 1.
Cost price of three bananas = Rs. 3
SP of three bananas = CP of five bananas = Rs. 5
Gain = SP - CP =  Rs. ( 5 - 3 ) = Rs. 2

                                                          Gain% = GainCP× 100% =  23× 100% = 2003 %= 6623%

Page No 160:

Question 10:

Fill in the blanks.

(i) Loss = (CP) − (......).
(ii) CP = 100×SP(......+......).
(iii) Profit or loss is always reckoned on ...... .
(iv) 100( 100-loss%)×SP=...... .

Answer:

(i) Loss = (CP) - (

SP

)

(ii) CP = 100 × SP( 100 + Gain%)

(iii) Profit or loss is always reckoned on

the cost price

.
(iv)  100 × SP(100 - loss%)   =

CP

Page No 160:

Question 11:

Write 'T' for true and 'F' for false

(i) Loss is reckoned on selling price.
(ii) Gain is reckoned on cost price.
(iii) CP=100×SP(100-loss%).
(iv) Loss = (CP) − (SP).

Answer:

(i) False
Gain or loss is always reckoned on the cost price.

   (ii) True
(iii) True
(iv) True

View NCERT Solutions for all chapters of Class 7

When a chair is sold at Rs 720 there is a loss of 10% at what price should it be sold to gain 25 %?

(d) Rs. 1440.

Is SP of a chair is Rs 720 a man gains 20% the CP of the chair?

Hence the cost price i.e. C.P of the chair is $ Rs. 600 $ . So, the correct answer is “ $ Rs. 600 $ ”.