Joelle had an equal number of dates and grapefruits at first. She sold one-third of the grapefruits and bought another 30 dates. In the end, she had thrice as many dates as grapefruits. Find the number of grapefruits she had at first.
| |
Grapefruits |
Dates |
| Before |
3 u |
6 u - 30 |
| Change |
- 1 u |
+ 30 |
| After |
2 u |
6 u |
The number of dates and grapefruits at first is the same.
6 u - 30 = 3 u
6 u - 3 u = 30
3 u = 30
1 u = 30 ÷ 3 = 10
Number of grapefruits that she had at first
= 3 u
= 3 x 10
= 30
Answer(s): 30
