At first, Ken had thrice as many sweets as Owen. After they each gave away 18 sweets, Ken had 7 times as many sweets as Owen. How many sweets did they have altogether at first?
| |
Ken |
Owen |
Difference |
| Before |
3x3 =
9 u |
1x3 =
3 u |
2x3 =
6 u |
| Change |
- 18 |
- 18 |
|
| After |
7 u |
1 u |
6 u |
Since they both gave away the same number of sweets, their difference in the number of sweets remains the same. Make the difference in the number of sweets the same. LCM of 2 and 6 is 6.
Number of sweets that each gave away
= 9 u - 7 u
= 2 u
2 u = 18
1 u = 18 ÷ 2 = 9
Number of sweets that they had altogether at first
= 9 u + 3 u
= 12 u
= 12 x 9
= 108
Answer(s): 108
