Simon, Pierre and Henry had the same number of balls. Henry gave 0.6 of his balls to Pierre. Then Pierre gave 0.25 of his balls to Simon. Finally, after Pierre gave 34 balls to Henry, he had the same number of balls as Henry. How many balls did Henry have at first?
| |
Simon |
Pierre |
Henry |
| Before |
1 u |
1 u |
1 u |
| Change 1 |
|
+ 0.6 u |
- 0.6 u |
| After 1 |
1 u |
1.6 u |
0.4 u |
| Change 2 |
+ 0.4 u |
- 0.4 u |
|
| After 2 |
1.4 u |
1.2 u |
0.4 u |
| Change 3 |
|
- 34 |
+ 34 |
| After 3 |
1.4 u |
1.2 u - 34 |
0.4 u + 34 |
Number of balls that Pierre gave to Simon
= 0.25 x 1.6 u
= 0.4 u
The number of balls that Pierre and Henry had in the end is the same.
1.2 u - 34 = 0.4 u + 34
1.2 u - 0.4 u = 34 + 34
0.8 u = 68
1 u = 68 ÷ 0.8 = 85
Number of balls that Henry had at first
= 1 u
= 85
Answer(s): 85
