Tim and Justin had a total of 120 marbles. Justin had half as many marbles as Tim. How many marbles must Tim give to Justin so they have an equal number of marbles?
| |
Tim |
Justin |
Total |
| Before |
2 u |
1 u |
120 |
| Change |
- ? |
+ ? |
|
| After |
1 |
1 |
|
Total number of marbles at first = 3 u
1 u = 120 ÷ 3 = 40
Tim and Justin have an equal number of marbles in the end.
Number of marbles that Justin has in the end
= 120 ÷ 2
= 60
Number of marbles that Tim must give to Justin
= 60 - 40
= 20
Answer(s): 20
