Fred had 5 times as many stamps as Zane at first. Then each of them bought an equal number of new stamps. In the end, Zane had 24 stamps and Fred had 4 times as many stamps as Zane. How many stamps did both of them buy altogether?
| |
Fred |
Zane |
Difference |
| Before |
5x3 =
15 u |
1x3 =
3 u |
4x3 =
12 u |
| Change |
+ ? |
+ ? |
|
| After |
4x4 =
16 u |
1x4 =
4 u |
3x4 =
12 u |
The difference in the number of stamps at first and in the end remains unchanged. Make the difference in the number of stamps at first and in the end the same. LCM of 4 and 3 is 12.
Number of stamps that Zane had in the end = 4 u
4 u = 24
1 u = 24 ÷ 4 = 6
Number of stamps that Fred bought
= 16 u - 15 u
= 1 u
Number of stamps that both of them bought altogether
= 2 x 1 u
= 2 u
= 2 x 6
= 12
Answer(s): 12
