There are 102 children in a parade square.
27 of the girls and
35 of the boys wear spectacles, there are 65 children in the parade square who do not wear spectacles. How many boys do not wear spectacles?
| |
Girls |
Boys |
Total |
| Do not wear spectacles |
5 u |
2 p |
65 |
| Wear spectacles |
2 u |
3 p |
37 |
| Total |
7 u |
5 p |
102 |
Number of children who wear spectacles
= 102 - 65
= 37
5 u + 2 p = 65 --- (1)
2 u + 3 p = 37 --- (2)
Make u the same.
(1)
x 2 10 u + 4 p = 130 --- (3)
(2)
x 5 10 u + 15 p = 185 --- (4)
(4) - (3)
(10 u + 15 p) - (10 u + 4 p) = 185 - 130
15 p - 4 p = 55
11 p = 55
1 p = 55 ÷ 11 = 5
Number of boys who do not wear spectacles
= 2 p
= 2 x 5
= 10
Answer(s): 10
