A store owner had the same number of mangoes, grapefruits and guavas at first. After 97 guavas, some mangoes and grapefruits were thrown away, there were 168 fruits left. There were four times as many mangoes as grapefruits left. The number of guavas left was 12 less than the number of mangoes. How many grapefruits were thrown away?
| |
Mangoes |
Grapefruits |
Guavas |
Total |
| Before |
1 |
1 |
1 |
|
| Change |
- ? |
- ? |
- 97 |
|
| After |
4 u |
1 u |
4 u - 12 |
168 |
Total number of fruits in the end
= 4 u + 1 u + 4 u - 12
= 9 u - 12
9 u - 12 = 168
9 u = 168 + 12
9 u = 180
1 u = 180 ÷ 9 = 20
Number of guavas at first
= 4 u - 12 + 97
= 4 x 20 - 12 + 97
= 80 - 12 + 97
= 165
The number of grapefruits and guavas at first was the same.
Number of grapefruits thrown away
= 165 - 1 u
= 165 - 20
= 145
Answer(s): 145
