A fruit stall had 4 times as many mangoes as grapefruits. After 4 mangoes were added, the number of mangoes became 25 more than the number of grapefruits. How many grapefruits were there at the fruit stall at first?
|
Mangoes |
Grapefruits |
Before |
4 u |
1 u |
Change |
+ 4 |
|
After |
4 u + 4 |
1 u |
If another 4 grapefruits are added, the number of mangoes and grapefruits will be the same.
4 u + 4 = 1 u + 25
4 u - 1 u = 25 - 4
3 u = 21
1 u = 21 ÷ 3 = 7
Number of grapefruits at the fruit stall at first
= 1 u
= 7
Answer(s): 7