A cake cost twice as much as a puff at a nearby eating house. Pierre spent 16 of his money on some puffs and half of the remaining sum on 5 cakes. He had $15 left.
- What was the cost of 1 puff?
- Justin bought 2 cakes and 4 puffs. How much did he spend altogether?
(a)
Fraction of Pierre's amount left after buying the puffs
= 1 -
16 =
56 Fraction of Pierre's amount spent on the cakes
=
56 x
12 =
512 Fraction of money left
= 1 -
16 -
512 = 1 -
212 -
512 =
512 Amount that Pierre had left = 5 u
5 u = 15
1 u = 15 ÷ 5 = 3
Amount that Pierre had left = Amount spent on 5 cakes
Cost of 5 cakes = $15
Cost of 1 cake = 15 ÷ 5 = $3
Cost of 1 cake is 2 times as much as the cost of 1 puff.
Cost of 1 puff
= 3 ÷ 2
= $1.50
(b)
Cost of 2 cakes and 4 puffs
= 2 x 3 + 4 x 1.50
= 6 + 6
= $12
Answer(s): (a) $1.50; (b) $12
