On a shelf, there were 52 sweaters and shirts. Bobby spilt soy milk on the shelf and stained 50% of the shirts and 25% of the sweaters. If 32 sweaters and shirts were still clean, how many clean shirts were there?
| |
Sweaters |
Shirts |
Total |
| Stained |
1 u |
1 p |
20 |
| Clean |
3 u |
1 p |
32 |
| Total |
4 u |
2 p |
52 |
50% =
50100 =
12 25% =
25100 =
14 Number of stained clothes
= 52 - 32
= 20
3 u + 1 p = 32
1 p = 32 - 3 u --- (1)
1 u + 1 p = 20
1 p = 20 - 1 u --- (2)
(2) - (1)
20 - 1 u = 32 - 3 u
3 u - 1 u = 32 - 20
2 u = 12
1 u = 12 ÷ 2 = 6
Number of clean shirts is the same as the number of stained shirts.
Number of clean shirts
= 20 - 1 u
= 20 - 6
= 14
Answer(s): 14
