Last Wednesday, Billy had thrice as many stamps as Tommy. Today, Billy gives 55 of his stamps to his neighbour. Now, Tommy has twice as many stamps as Billy. How many stamps does Tommy have?
| |
Billy |
Tommy |
| Before |
3x2 =
6 u |
1x2 =
2 u |
| Change |
- 55 |
|
| After |
1 u |
2 u |
The number of stamps that Tommy had at first and in the end remains unchanged. Make the number of stamps that Tommy has the same. LCM of 1 and 2 is 2.
Number of stamps that Billy gives to his neighbour
= 6 u - 1 u
= 5 u
5 u = 55
1 u = 55 ÷ 5 = 11
Number of stamps that Tommy has
= 2 u
= 2 x 11
= 22
Answer(s): 22
