On a shelf, there were 115 shirts and hoodies. Simon spilt coffee on the shelf and stained 50% of the hoodies and 20% of the shirts. If 83 shirts and hoodies were still clean, how many clean hoodies were there?
| |
Shirts |
Hoodies |
Total |
| Stained |
1 u |
1 p |
32 |
| Clean |
4 u |
1 p |
83 |
| Total |
5 u |
2 p |
115 |
50% =
50100 =
12 20% =
20100 =
15 Number of stained clothes
= 115 - 83
= 32
4 u + 1 p = 83
1 p = 83 - 4 u --- (1)
1 u + 1 p = 32
1 p = 32 - 1 u --- (2)
(2) - (1)
32 - 1 u = 83 - 4 u
4 u - 1 u = 83 - 32
3 u = 51
1 u = 51 ÷ 3 = 17
Number of clean hoodies is the same as the number of stained hoodies.
Number of clean hoodies
= 32 - 1 u
= 32 - 17
= 15
Answer(s): 15
