Mr Justin bought some pizzas for a group of children. There was an equal number of boys and girls. The boys received 4 times as many pizzas as the girls. Each girl ate
15 of a pizza and the girls finished all the pizzas given to them. Each boy ate
110 of a pizza and the boys had 15
25 pizzas left. How many pizzas did Mr Justin buy?
|
Boys (1) |
Girls (2) |
Before |
4 u |
1 u |
Change |
- 1 p |
- 2 p |
After |
154 |
0 |
15 =
210 Cutting the slices of pizzas into same size. Each pizza was cut into 10 slices. Every boy ate 1 slice of pizza and every girl ate 2 slices of pizza.
Number of slices that the boys had left
= 15
25 ÷
110 =
775 x 10
= 154
4 u - 1 p = 154 --- (1)
1 u - 2 p = 0
1 u = 2 p --- (2)
Make u the same.
(2)
x44 u = 8 p --- (3)
Substitute (3) into (1).
4 u - 1 p = 154
8 p - 1 p = 154
7 p = 154
1 p = 154 ÷ 7 = 22
Total number of slices of pizzas for boys
= 154 + 1 p
= 154 + 22
= 176
Total number of slices of pizzas for girls
= 176 ÷ 4
= 44
Total number of slices of pizzas for children
= 176 + 44
= 220
Total number of pizzas that Mr Justin bought
= 220 ÷ 10
= 22
Answer(s): 22