A fruit stall had 3 times as many guavas as mangosteens. After 12 guavas were added, the number of guavas became 20 more than the number of mangosteens. How many mangosteens were there at the fruit stall at first?
| |
Guavas |
Mangosteens |
| Before |
3 u |
1 u |
| Change |
+ 12 |
|
| After |
3 u + 12 |
1 u |
If another 12 mangosteens are added, the number of guavas and mangosteens will be the same.
3 u + 12 = 1 u + 20
3 u - 1 u = 20 - 12
2 u = 8
1 u = 8 ÷ 2 = 4
Number of mangosteens at the fruit stall at first
= 1 u
= 4
Answer(s): 4
