Vincent had twice as many marbles as Fabian. After Fabian lost 18 marbles and Vincent bought 18 marbles, Vincent had 4 times as many marbles as Fabian. How many marbles did Vincent and Fabian have altogether at first?
| |
Vincent |
Fabian |
Total |
| Before |
2x5 =
10 u |
1x5 =
5 u |
3x5 =
15 u |
| Change |
+ 18 |
- 18 |
|
| After |
4x3 =
12 u |
1x3 =
3 u |
5x3 =
15 u |
The number of marbles that Fabian lost and bought is the same. So, the total number of marbles remains unchanged. Make the total number of marbles the same. LCM of 3 and 5 is 15.
Number of marbles that Vincent bought
= 12 u - 10 u
= 2 u
2 u = 18
1 u = 18 ÷ 2 = 9
Number of cards that they had altogether at first
= 15 u
= 15 x 9
= 135
Answer(s): 135
