Question

The cost price of 20 notebooks is the same as the selling price of x of those notebooks. If the profit is 25%, what is the value of x?

Answer 1

Thanks for asking this question let me help you in finding the answer.
Let the cost price of each notebook is 1.
 then cost price of X article = Rs x
Sale price of X article is = Rs.20
Profit will be= Rs. (20 - X)           as profit is 25%
So hence 20 - X/X *100 =25
then 2000 - 100X = 25X
125X= 2000

So finally we will got X= 16
16 rupees will be the price of notebooks.
Hope this will help you.

Answer 2

Solution :-

Let Cost price of each notebook be Rs. 1.

Then, Cost price of x notebooks will be Rs. x

And, selling price of x notebooks = Rs. 20

Profit = Rs. (20 - x)

⇒ (20 - x)*100/x = 25

⇒ (2000 - 100x) = 25x

⇒ 2000 - 100x = 25x

⇒ 2000 = 25x + 100x

⇒ 2000 = 125x

⇒ x = 2000/125

⇒ x = Rs. 16

Answer.