There are 201 children in a school field.
38 of the girls and
47 of the boys wear hats, there are 116 children in the school field who do not wear hats. How many boys wear hats?
| |
Girls |
Boys |
Total |
| Do not wear hats |
5 u |
3 p |
116 |
| Wear hats |
3 u |
4 p |
85 |
| Total |
8 u |
7 p |
201 |
Number of children who wear hats
= 201 - 116
= 85
5 u + 3 p = 116 --- (1)
3 u + 4 p = 85 --- (2)
Make u the same.
(1)
x 3 15 u + 9 p = 348 --- (3)
(2)
x 5 15 u + 20 p = 425 --- (4)
(4) - (3)
(15 u + 20 p) - (15 u + 9 p) = 425 - 348
20 p - 9 p = 77
11 p = 77
1 p = 77 ÷ 11 = 7
Number of boys who wear hats
= 4 p
= 4 x 7
= 28
Answer(s): 28
