Problem 7 · 2021 Math Kangaroo
Medium
Logic & Word Problems
careful-counting
These children are standing in a line. Some are facing forwards and others are facing backwards. How many children are holding another child's hand with their right hand?
Show answer
Answer: E — 6
Show hints
Hint 1 of 3
Which hand is a child's right hand depends on which way that child is facing.
Still stuck? Show hint 2 →
Hint 2 of 3
For a child facing you, the right hand is on your left side; for one facing away, it is on your right side.
Still stuck? Show hint 3 →
Hint 3 of 3
Go child by child and only count the ones whose right hand is holding a neighbour.
Show solution
Approach: check each child's facing direction
- Look at each child and decide which hand is the right hand based on whether they face front or back.
- Now count only the children whose right hand is the one holding a neighbour's hand.
- Counting them all up gives 6 children.
Mark:
· log in to save