On a shelf, there were 222 cardigans and shirts. Justin spilt soy milk on the shelf and stained 50% of the shirts and 10% of the cardigans. If 187 cardigans and shirts were still clean, how many clean shirts were there?
| |
Cardigans |
Shirts |
Total |
| Stained |
1 u |
1 p |
35 |
| Clean |
9 u |
1 p |
187 |
| Total |
10 u |
2 p |
222 |
50% =
50100 =
12 10% =
10100 =
110 Number of stained clothes
= 222 - 187
= 35
9 u + 1 p = 187
1 p = 187 - 9 u --- (1)
1 u + 1 p = 35
1 p = 35 - 1 u --- (2)
(2) - (1)
35 - 1 u = 187 - 9 u
9 u - 1 u = 187 - 35
8 u = 152
1 u = 152 ÷ 8 = 19
Number of clean shirts is the same as the number of stained shirts.
Number of clean shirts
= 35 - 1 u
= 35 - 19
= 16
Answer(s): 16
