There was an equal number of starfruits and mangoes. On Tuesday, some starfruits were added, such that the number of starfruits increased by 80%. On Wednesday, the number of starfruits further increased by 50% and the number of mangoes decreased by 10%. There were 72 more starfruits than mangoes in the end. How many starfruits and mangoes were there altogether at first?
|
Starfruits |
Mangoes |
Before |
1 u |
1 u |
Change 1 |
+ 0.8 u |
No change |
After 1 |
1.8 u |
1 u |
Change 2 |
+ 0.9 u |
- 0.1 u |
After 2 |
2.7 u |
0.9 u |
Number of starfruits added on Tuesday
= 80% x 1 u
=
80100 x 1 u
= 0.8 u
Number of starfruits increased on Wednesday
= 50% x 1.8 u
=
50100 x 1.8 u
= 0.9 u
Number of mangoes decreased on Wednesday
= 10% x 1 u
=
10100 x 1 u
= 0.1 u
Number of more starfruits than mangoes in the end
= 2.7 u - 0.9 u
= 1.8 u
1.8 u = 72
1 u = 72 ÷ 1.8 = 40
Total number of starfruits and mangoes at first
= 1 u + 1 u
= 2 u
= 2 x 40
= 80
Answer(s): 80