On a shelf, there were 78 cardigans and hoodies. Andy spilt hot tea on the shelf and stained 50% of the hoodies and 10% of the cardigans. If 67 cardigans and hoodies were still clean, how many stained hoodies were there?
| |
Cardigans |
Hoodies |
Total |
| Stained |
1 u |
1 p |
11 |
| Clean |
9 u |
1 p |
67 |
| Total |
10 u |
2 p |
78 |
50% =
50100 =
12 10% =
10100 =
110 Number of stained clothes
= 78 - 67
= 11
9 u + 1 p = 67
1 p = 67 - 9 u --- (1)
1 u + 1 p = 11
1 p = 11 - 1 u --- (2)
(2) - (1)
11 - 1 u = 67 - 9 u
9 u - 1 u = 67 - 11
8 u = 56
1 u = 56 ÷ 8 = 7
Number of stained hoodies
= 11 - 1 u
= 11 - 7
= 4
Answer(s): 4
