On a shelf, there were 82 skirts and cardigans. Neave spilt hot coffee on the shelf and stained 50% of the cardigans and 20% of the skirts. If 62 skirts and cardigans were still clean, how many stained cardigans were there?
| |
Skirts |
Cardigans |
Total |
| Stained |
1 u |
1 p |
20 |
| Clean |
4 u |
1 p |
62 |
| Total |
5 u |
2 p |
82 |
50% =
50100 =
12 20% =
20100 =
15 Number of stained clothes
= 82 - 62
= 20
4 u + 1 p = 62
1 p = 62 - 4 u --- (1)
1 u + 1 p = 20
1 p = 20 - 1 u --- (2)
(2) - (1)
20 - 1 u = 62 - 4 u
4 u - 1 u = 62 - 20
3 u = 42
1 u = 42 ÷ 3 = 14
Number of stained cardigans
= 20 - 1 u
= 20 - 14
= 6
Answer(s): 6
