There were 167 blue, red and gold markers in a box. 17 gold markers were removed from the box and the ratio of the number of blue markers to the number of red markers to the number of gold markers became 5 : 2 : 3. Then some white markers were added and the ratio of the number of gold markers to the number of white markers was 3 : 9.
- What was the ratio of the number of blue markers to the number of red markers to the number of gold markers at first?
- How many markers were in the box in the end?
|
Blue |
Red |
Gold |
White |
Total |
Before |
5 u |
2 u |
3 u + 17 |
0 |
167 |
Change 1 |
No change |
No change |
- 17 |
|
- 17 |
After 1 |
5 u |
2 u |
3 u |
|
150 |
Change 2 |
No change |
No change |
No change |
+ 9 u |
|
After 2 |
5 u |
2 u |
3 u |
9 u |
|
(a)
Total number of markers at first
= 5 u + 2 u + 3 u + 17
= 10 u + 17
10 u + 17 = 167
10 u = 167 - 17
10 u = 150
1 u = 150 ÷ 10 = 15
Number of blue markers at first
= 5 u
= 5 x 15
= 75
Number of red markers at first
= 2 u
= 2 x 15
= 30
Number of gold markers at first
= 3 u + 17
= 3 x 15 + 17
= 62
At first
Blue markers : Red markers : Gold markers
75 : 30 : 62
(b)
Total number of markers in the box in the end
= 5 u + 2 u + 3 u + 9 u
= 19 u
= 285
Answer(s): (a) 75 : 30 : 62; (b) 285