Answer:
2 kiwis per cup
Explanation:
Both have the same number of fruits= 40 pieces of fruit fruits (Because Susan has 25 strawberries and 15 kiwis)
5 cups and 4 cups should have a common multiple of 40
40/5= 8 (5 strawberries + 3 kiwi) 8 piece of fruit per cup
40/4 = 10 (8 strawberries +2 kiwi) 10 piece of fruit per cup
We only knew that in each cup Joanna uses 8 strawberries per cup
(10-8=2) Now we know she uses 2 kiwis per cup
Total 32 strawberries (4x8) and 8 kiwis (4x2)= 40 pieces of fruit