Question

Monika bought 100 chickens each for rs. 80 and sold 20 of them at a gain of 5%. at what gain percent must she sell the remaining chickens so as to gain 20% on the whole


give me full explanation ​

Answer 1

Answer:

Given, Toshiba bought 100 hens for Rs. 8000

and sold 20 at gain = 5 %

to gain 20 % in whole.

Cost price (CP) of 100 hens = Rs 8000

Cost price of 1 hen =

100

8000

=Rs.80

So, cost price of 20 hens =20×80

=Rs.1600

Gain % =

CP

SP−CP

×100

5=

1600

SP−1600

×100

SP=

100

5×1600

+1600=Rs.1680

∴ Gain on 20 hens = (1680 - 1600) = Rs .80

Now, cost price of 80 hens =80×80

=Rs.6400

Gain on 80 hens = ( SP - CP) of 80 hens

Gain on 100 hens = gain on 80 hens + gain on 20 hens

∴ Gain on 100 hens = (SP - CP) of 80 hens + 80

Gain % on 100 hens =

CP of hens

Gain on 100 hens

×100

∴20=

8000

(SP of 80 hens - 6400 + 80 )

×100

∴ SP of 80 hens =

100

8000×20

+6400−80

=1600+6400−80=Rs.7920

∴ Gain of 80 hens =7920−6400

=Rs.1520

∴

C.P. of 80 hens

Gain on 80 hens

×100=gain %=

6400

1520

×100=23.75%

So, the remaining hens should be sold at 23.75 % gain percent.

Answer 2

Answer:

23.75 %

Step-by-step explanation:

monika bought 100 chicken at the rate of rs. 80

so, 100×80= rs. 8000 (C.P)

20 chickens rate= 20×80 = rs. 1600

20 chickens s.p 5% gain = (5% of 1600) +1600

= (5/100×1600)+1600

= 80+1600

=rs. 1680

remaining chickens =80×80=rs. 6400

let the gain % be x%

6400 + x% of 6400

6400 + x/100 ×6400

6400+64x

total gain on the whole = 20%

total c.p = rs. 8000

total s.p = 6400 + 64x + 1680

= 8080 + 64x

gain% = (s.p-c.p) ×100/8000

20. = 8080+64x-8000× 100/8000

20. = 80+64x ×100/8000

20×8000/100 = 80+64x

1600. = 80+64x

1600-80 = 64x

1520 = 64x

1520/64 = x

95/4 = x

23.75 = x

so the answer is 23.75 %

thankyou

myself Ashakiran from class 8th