Problem 9 · 2015 Math Kangaroo
Medium
Algebra & Patterns
work-backward
Luis has got 7 apples and 2 bananas. He gives 2 apples to his friend Jacob, who gives him bananas in return. Afterwards Luis has got the same amount of apples as bananas. How many bananas did Luis get from Jacob?
Show answer
Answer: B — 3
Show hints
Hint 1 of 2
First update the apple count after Luis gives 2 away.
Still stuck? Show hint 2 →
Hint 2 of 2
Set the new banana count equal to the apple count and read off how many bananas he received.
Show solution
Approach: track apples and bananas, then make them equal
- Luis gives away 2 of his 7 apples, leaving 5 apples.
- Afterwards he has as many bananas as apples, so he must have 5 bananas.
- He started with 2 bananas, so he received 5 − 2 = 3 bananas from Jacob.
- The answer is 3.
Mark:
· log in to save