Eric is selling 800 story books. He sold 50% of them at $12 each, 20% of the remainder at a discount of 25% and the rest at cost price. He made a profit of $2350. Find the cost price of a story book.
| Price |
$12 |
$9 |
Cost Price |
| Percent |
50% |
50% |
| |
|
10% |
40% |
| Number |
400 |
80 |
Not needed |
| Amount collected |
$4800 |
$720 |
Not needed |
Number of story books sold at $12
= 50% x 800
=
50100 x 800
= 400
Price after 25% discount
= 75% x 12
=
75100 x 12
= $9
Remaining story books
= 800 - 400
= 400
Number of story books sold at $9
= 20% x 400
=
20100 x 400
= 80
Number of story books sold at $12 or 25% discount
= 400 + 80
= 480
Total amount collected from the sale of 400 story books
= 400 x 12
= $4800
Total amount collected from the sale of the other 80 story books
= 80 x 9
= $720
Total amount collected from the sale of story books sold at $12 or 25% discount
= 4800 + 720
= $5520
Cost price of 480 story books
= 5520 - 2350
= $960
Cost price of 1 story book
= 960 ÷ 480
= $2
Answer(s): $2
