Will had 6 times as many buttons as Daniel at first. Then each of them bought an equal number of new buttons. In the end, Daniel had 15 buttons and Will had 4 times as many buttons as Daniel. How many buttons did both of them buy altogether?
| |
Will |
Daniel |
Difference |
| Before |
6x3 =
18 u |
1x3 =
3 u |
5x3 =
15 u |
| Change |
+ ? |
+ ? |
|
| After |
4x5 =
20 u |
1x5 =
5 u |
3x5 =
15 u |
The difference in the number of buttons at first and in the end remains unchanged. Make the difference in the number of buttons at first and in the end the same. LCM of 5 and 3 is 15.
Number of buttons that Daniel had in the end = 5 u
5 u = 15
1 u = 15 ÷ 5 = 3
Number of buttons that Will bought
= 20 u - 18 u
= 2 u
Number of buttons that both of them bought altogether
= 2 x 2 u
= 4 u
= 4 x 3
= 12
Answer(s): 12
