Barbara spent
512 of her money on 4 wafers and 7 puffs. If each wafer costs twice as much as a puff, how many puffs could Barbara buy with the rest of her money?
| |
Wafers |
Puffs |
| Number |
4 |
7 |
| Value |
2 u |
1 u |
| Total value |
8 u |
7 u |
Cost of 1 puff = 1 u
Cost of 1 wafer = 2 u
Total cost of 4 wafers and 7 puffs
= 4 x 2 u + 7 x 1 u
= 15 u
Fraction of Barbara's money left
= 1 -
512 =
712512 of Barbara's money = 15 u
112 of Barbara's money = 15 u ÷ 5 = 3 u
712 of Barbara's money = 3 u x 7 = 21 u
Number of puffs that Barbara could buy
= 21 u ÷ 1 u
= 21
Answer(s): 21
