Neave had 5 times as many erasers as Sean at first. Then each of them bought an equal number of new erasers. In the end, Sean had 22 erasers and Neave had 3 times as many erasers as Sean. How many erasers did both of them buy altogether?
| |
Neave |
Sean |
Difference |
| Before |
5x1 =
5 u |
1x1 =
1 u |
4x1 =
4 u |
| Change |
+ ? |
+ ? |
|
| After |
3x2 =
6 u |
1x2 =
2 u |
2x2 =
4 u |
The difference in the number of erasers at first and in the end remains unchanged. Make the difference in the number of erasers at first and in the end the same. LCM of 4 and 2 is 4.
Number of erasers that Sean had in the end = 2 u
2 u = 22
1 u = 22 ÷ 2 = 11
Number of erasers that Neave bought
= 6 u - 5 u
= 1 u
Number of erasers that both of them bought altogether
= 2 x 1 u
= 2 u
= 2 x 11
= 22
Answer(s): 22
