Mr Zane bought some pizzas for a group of students. There was an equal number of girls and boys. The girls received 5 times as many pizzas as the boys. Each boy ate
16 of a pizza and the boys finished all the pizzas given to them. Each girl ate
112 of a pizza and the girls had 14
14 pizzas left. How many pizzas did Mr Zane buy?
|
Girls (1) |
Boys (2) |
Before |
5 u |
1 u |
Change |
- 1 p |
- 2 p |
After |
171 |
0 |
16 =
212 Cutting the slices of pizzas into same size. Each pizza was cut into 12 slices. Every girl ate 1 slice of pizza and every boy ate 2 slices of pizza.
Number of slices that the girls had left
= 14
14 ÷
112 =
574 x 12
= 171
5 u - 1 p = 171 --- (1)
1 u - 2 p = 0
1 u = 2 p --- (2)
Make u the same.
(2)
x55 u = 10 p --- (3)
Substitute (3) into (1).
5 u - 1 p = 171
10 p - 1 p = 171
9 p = 171
1 p = 171 ÷ 9 = 19
Total number of slices of pizzas for girls
= 171 + 1 p
= 171 + 19
= 190
Total number of slices of pizzas for boys
= 190 ÷ 5
= 38
Total number of slices of pizzas for students
= 190 + 38
= 228
Total number of pizzas that Mr Zane bought
= 228 ÷ 12
= 19
Answer(s): 19