David and Will had a total of 42 coins. Will had half as many coins as David. How many coins must David give to Will so they have an equal number of coins?
| |
David |
Will |
Total |
| Before |
2 u |
1 u |
42 |
| Change |
- ? |
+ ? |
|
| After |
1 |
1 |
|
Total number of coins at first = 3 u
1 u = 42 ÷ 3 = 14
David and Will have an equal number of coins in the end.
Number of coins that Will has in the end
= 42 ÷ 2
= 21
Number of coins that David must give to Will
= 21 - 14
= 7
Answer(s): 7
