Penelope bought some Social Science books at $19 each. She also bought an equal number of English books at a different price. The average price of one Social Science and one English book was $12. Penelope paid $70 more for the Social Science books than the English books.
- What was the cost of one English book?
- How many Social Science books did Penelope buy?
|
Social Science |
English |
More |
Number |
1 u |
1 u |
|
Value |
$19 |
$5 |
|
Total value |
19 u |
5 u |
$70 |
(a)
Price of one English book
= 2 x 12 - 19
= 24 - 19
= $5
Amount that Penelope paid more for Social Science books than English books
= 19 u - 5 u
= 14 u
14 u = 70
1 u = 70 ÷ 14 = 5
Number of Social Science books that Penelope bought
= 1 u
= 5
Answer(s): (a) $5; (b) 5