Oliver is selling 700 fiction books. He sold 60% of them at $10 each, 30% of the remainder at a discount of 40% and the rest at cost price. He made a profit of $2129. Find the cost price of a fiction book.
| Price |
$10 |
$6 |
Cost Price |
| Percent |
60% |
40% |
| |
|
12% |
28% |
| Number |
420 |
84 |
Not needed |
| Amount collected |
$4200 |
$504 |
Not needed |
Number of fiction books sold at $10
= 60% x 700
=
60100 x 700
= 420
Price after 40% discount
= 60% x 10
=
60100 x 10
= $6
Remaining fiction books
= 700 - 420
= 280
Number of fiction books sold at $6
= 30% x 280
=
30100 x 280
= 84
Number of fiction books sold at $10 or 40% discount
= 420 + 84
= 504
Total amount collected from the sale of 420 fiction books
= 420 x 10
= $4200
Total amount collected from the sale of the other 84 fiction books
= 84 x 6
= $504
Total amount collected from the sale of fiction books sold at $10 or 40% discount
= 4200 + 504
= $4704
Cost price of 504 fiction books
= 4704 - 2129
= $4536
Cost price of 1 fiction book
= 4536 ÷ 504
= $9
Answer(s): $9
