There were some grey, brown and black staplers in a box.
19 of the staplers were brown. The ratio of the number of grey staplers to the number of black staplers was 3 : 5. There were 288 fewer brown staplers than black staplers.
- Find the ratio of the number of grey staplers to the number of brown staplers to the number of black staplers in the box.
- How many black staplers were there?
Brown |
Grey |
Black |
Total |
1 |
8 |
9 |
|
3 |
5 |
|
1 u |
3 u |
5 u |
9 u |
(a)
Grey : Brown : Black
3 : 1 : 5
(b)
Number of fewer brown staplers than black staplers
= 5 u - 1 u
= 4 u
4 u = 288
1 u = 288 ÷ 4 = 72
Number of black staplers
= 5 u
= 5 x 72
= 360
Answer(s): (a) 3 : 1 : 5; (b) 360