There were 195 silver, red and purple staplers in a box. 8 purple staplers were removed from the box and the ratio of the number of silver staplers to the number of red staplers to the number of purple staplers became 5 : 3 : 9. Then some grey staplers were added and the ratio of the number of purple staplers to the number of grey staplers was 9 : 5.
- What was the ratio of the number of silver staplers to the number of red staplers to the number of purple staplers at first?
- How many staplers were in the box in the end?
|
Silver |
Red |
Purple |
Grey |
Total |
Before |
5 u |
3 u |
9 u + 8 |
0 |
195 |
Change 1 |
No change |
No change |
- 8 |
|
- 8 |
After 1 |
5 u |
3 u |
9 u |
|
187 |
Change 2 |
No change |
No change |
No change |
+ 5 u |
|
After 2 |
5 u |
3 u |
9 u |
5 u |
|
(a)
Total number of staplers at first
= 5 u + 3 u + 9 u + 8
= 17 u + 8
17 u + 8 = 195
17 u = 195 - 8
17 u = 187
1 u = 187 ÷ 17 = 11
Number of silver staplers at first
= 5 u
= 5 x 11
= 55
Number of red staplers at first
= 3 u
= 3 x 11
= 33
Number of purple staplers at first
= 9 u + 8
= 9 x 11 + 8
= 107
At first
Silver staplers : Red staplers : Purple staplers
55 : 33 : 107
(b)
Total number of staplers in the box in the end
= 5 u + 3 u + 9 u + 5 u
= 22 u
= 242
Answer(s): (a) 55 : 33 : 107; (b) 242