Xylia had a collection of 1800 grey, brown and white balls. After Xylia gave away 320 grey balls, the number of grey balls was 200 fewer than the number of brown balls. Given that the number of white balls was five times as many as the number of brown balls, how many grey balls did Xylia have at first?
| |
Grey balls |
Brown balls |
White balls |
Total |
| Before |
1 u + 320 |
1 u + 200 |
5 u + 1000 |
1800 |
| Change |
- 320 |
|
|
|
| After |
1 u |
1 u + 200 |
5 u + 1000 |
|
Number of white balls in the end
= 5 x (1 u + 200)
= 5 u + 1000
Total number of balls at first
= 1 u + 320 + 1 u + 200 + 5 u + 1000
= 7 u + 1520
7 u + 1520 = 1800
7 u = 1800 - 1520
7 u = 280
1 u = 280 ÷ 7 = 40
Number of grey balls that Xylia had at first
= 1 u + 320
= 40 + 320
= 360
Answer(s): 360
