On a shelf, there were 160 sweaters and shirts. Gabriel spilt coffee on the shelf and stained 50% of the shirts and 10% of the sweaters. If 132 sweaters and shirts were still clean, how many clean shirts were there?
| |
Sweaters |
Shirts |
Total |
| Stained |
1 u |
1 p |
28 |
| Clean |
9 u |
1 p |
132 |
| Total |
10 u |
2 p |
160 |
50% =
50100 =
12 10% =
10100 =
110 Number of stained clothes
= 160 - 132
= 28
9 u + 1 p = 132
1 p = 132 - 9 u --- (1)
1 u + 1 p = 28
1 p = 28 - 1 u --- (2)
(2) - (1)
28 - 1 u = 132 - 9 u
9 u - 1 u = 132 - 28
8 u = 104
1 u = 104 ÷ 8 = 13
Number of clean shirts is the same as the number of stained shirts.
Number of clean shirts
= 28 - 1 u
= 28 - 13
= 15
Answer(s): 15
