During a telematch, each group of pupils was supposed to collect as many coloured balls as possible. Each colour represented a certain point as tabulated:
| Colours |
Points |
| Red |
3 |
| Yellow |
4 |
| Purple |
5 |
In each container, the number of red balls was 60% more than the number of purple balls and 50% less than the number of yellow balls. Given that the total possible points if the group managed to collect all the balls were 791 points, how many balls were not red in colour?
| Red |
Yellow |
Purple |
| 8x1 |
|
5x1 |
| 1x8 |
2x8 |
|
| 8 u |
16 u |
5 u |
| |
Red |
Yellow |
Purple |
Total |
| Number |
8 u |
16 u |
5u |
|
| Value |
3 |
4 |
5 |
|
| Total value |
24 u |
64 u |
25 u |
113 u |
100% + 60% = 160%
160% =
160100 =
85 100% - 50% = 50%
50% =
50100 =
12 Total number of points collected
= 24 u + 64 u + 25 u
= 113 u
113 u = 791
1 u = 791 ÷ 113 = 7
Number of balls not red in colour
= 16 u + 5 u
= 21 u
= 21 x 7
= 147
Answer: 147
