Last Wednesday, Jack had twice as many coins as John. Today, Jack gives 28 of his coins to his buddy. Now, John has four times as many coins as Jack. How many coins does John have?
| |
Jack |
John |
| Before |
2x4 =
8 u |
1x4 =
4 u |
| Change |
- 28 |
|
| After |
1 u |
4 u |
The number of coins that John had at first and in the end remains unchanged. Make the number of coins that John has the same. LCM of 1 and 4 is 4.
Number of coins that Jack gives to his buddy
= 8 u - 1 u
= 7 u
7 u = 28
1 u = 28 ÷ 7 = 4
Number of coins that John has
= 4 u
= 4 x 4
= 16
Answer(s): 16
