The bookstore bought two books for $45, with a profit of 40%. find the cost of each book if the first book's profit was 25% and the second one's profit was 50%.

Cost of first book is $18

Cost of second book is $27

Step-by-step explanation:

Given : The bookstore bought two books for $45, with a profit of 40%. If the first book's profit was 25% and the second one's profit was 50%.

To find : The cost of each book.

Solution :

Let x be the cost of first book.

Let y be the cost of second book.

The bookstore bought two books for $45

i.e, .......[1]

The first book's profit was 25%

i.e, 25% of x is  

The second one's profit was 50%.

i.e, 50% of y is  

Book bought at $45 with profit 40%

i.e, .......[2]

Solving equation [1] and [2]

Substitute x=45-y from [1] in [2]

Put back in [1]

Therefore, Cost of first book is $18

Cost of second book is $27

both equations and proportions are better.

answer: do we write it

step-by-step explanation: