Mary spent
511 of her money on 8 puffs and 9 shortbreads. If each puff costs twice as much as a shortbread, how many puffs could Mary buy with the rest of her money?
| |
Puffs |
Shortbreads |
| Number |
8 |
9 |
| Value |
2 u |
1 u |
| Total value |
16 u |
9 u |
Cost of 1 shortbread = 1 u
Cost of 1 puff = 2 u
Total cost of 8 puffs and 9 shortbreads
= 8 x 2 u + 9 x 1 u
= 25 u
Fraction of Mary's money left
= 1 -
511 =
611511 of Mary's money = 25 u
111 of Mary's money = 25 u ÷ 5 = 5 u
611 of Mary's money = 5 u x 6 = 30 u
Number of puffs that Mary could buy
= 30 u ÷ 2 u
= 15
Answer(s): 15
