Last Tuesday, Luke had thrice as many marbles as Archie. Today, Luke gives 50 of his marbles to his sister. Now, Archie has twice as many marbles as Luke. How many marbles does Archie have?
| |
Luke |
Archie |
| Before |
3x2 =
6 u |
1x2 =
2 u |
| Change |
- 50 |
|
| After |
1 u |
2 u |
The number of marbles that Archie had at first and in the end remains unchanged. Make the number of marbles that Archie has the same. LCM of 1 and 2 is 2.
Number of marbles that Luke gives to his sister
= 6 u - 1 u
= 5 u
5 u = 50
1 u = 50 ÷ 5 = 10
Number of marbles that Archie has
= 2 u
= 2 x 10
= 20
Answer(s): 20
