Tim had 5 times as many coins as Cole at first. Then each of them bought an equal number of new coins. In the end, Cole had 36 coins and Tim had 4 times as many coins as Cole. How many coins did both of them buy altogether?
| |
Tim |
Cole |
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 coins at first and in the end remains unchanged. Make the difference in the number of coins at first and in the end the same. LCM of 4 and 3 is 12.
Number of coins that Cole had in the end = 4 u
4 u = 36
1 u = 36 ÷ 4 = 9
Number of coins that Tim bought
= 16 u - 15 u
= 1 u
Number of coins that both of them bought altogether
= 2 x 1 u
= 2 u
= 2 x 9
= 18
Answer(s): 18
