There were 104 brown, black and gold markers in a box. 6 gold markers were removed from the box and the ratio of the number of brown markers to the number of black markers to the number of gold markers became 4 : 3 : 7. Then some purple markers were added and the ratio of the number of gold markers to the number of purple markers was 7 : 3.
- What was the ratio of the number of brown markers to the number of black markers to the number of gold markers at first?
- How many markers were in the box in the end?
|
Brown |
Black |
Gold |
Purple |
Total |
Before |
4 u |
3 u |
7 u + 6 |
0 |
104 |
Change 1 |
No change |
No change |
- 6 |
|
- 6 |
After 1 |
4 u |
3 u |
7 u |
|
98 |
Change 2 |
No change |
No change |
No change |
+ 3 u |
|
After 2 |
4 u |
3 u |
7 u |
3 u |
|
(a)
Total number of markers at first
= 4 u + 3 u + 7 u + 6
= 14 u + 6
14 u + 6 = 104
14 u = 104 - 6
14 u = 98
1 u = 98 ÷ 14 = 7
Number of brown markers at first
= 4 u
= 4 x 7
= 28
Number of black markers at first
= 3 u
= 3 x 7
= 21
Number of gold markers at first
= 7 u + 6
= 7 x 7 + 6
= 55
At first
Brown markers : Black markers : Gold markers
28 : 21 : 55
(b)
Total number of markers in the box in the end
= 4 u + 3 u + 7 u + 3 u
= 17 u
= 119
Answer(s): (a) 28 : 21 : 55; (b) 119