Mary had an equal number of apples and plums at first. She sold half of the plums and bought another 84 apples. In the end, she had four times as many apples as plums. Find the number of plums she had at first.
| |
Plums |
Apples |
| Before |
2 u |
4 u - 84 |
| Change |
- 1 u |
+ 84 |
| After |
1 u |
4 u |
The number of apples and plums at first is the same.
4 u - 84 = 2 u
4 u - 2 u = 84
2 u = 84
1 u = 84 ÷ 2 = 42
Number of plums that she had at first
= 2 u
= 2 x 42
= 84
Answer(s): 84
