Henry has 210 marbles and Flynn has 428 marbles. How many marbles must Flynn give to Henry so that Henry will have 66 less marbles than Flynn?
|
Henry |
Flynn |
Total |
Before |
210 |
428 |
638 |
Change |
+ ? |
- ? |
|
After |
1 u |
1 u + 66 |
638 |
The total number of marbles remains unchanged after Flynn gives to Henry.
Total number of marbles
= 210 + 428
= 638
Total number of marbles in the end
= 1 u + 1 u + 66
= 2 u + 66
2 u + 66 = 638
2 u = 638 - 66
2 u = 572
1 u = 572 ÷ 2 = 286
Number of marbles that Flynn must give to Henry
= 286 - 210
= 76
Answer(s): 76