Archie has
57 as many erasers as Andy. They have a total of 252 erasers. How many erasers must Andy give to Archie so that they will have the same number of erasers?
|
Archie |
Andy |
Total |
Before |
5 u |
7 u |
12 u |
Change |
+ ? |
- ? |
|
After |
126 |
126 |
252 |
Total number of erasers
= 5 u + 7 u
= 12 u
12 u = 252
1 u = 252 ÷ 12 = 21
Number of erasers that each of them has in the end
= 252 ÷ 2
= 126
Number of erasers that Archie has
= 5 u
= 5 x 21
= 105
Number of erasers that Andy must give Archie
= 126 - 105
= 21
Answer(s): 21