Coco builds a mobile: layer has one hanger; each hanger has two new hangers on the next layer. She stops after completing layers. How many hangers are in the mobile altogether?
Select one option, then click Submit.
Between 20 and 30
Between 30 and 40
Between 40 and 50
Between 50 and 60
Between 60 and 70
Select an option, then submit.
Sign in or create an account to reveal answers, view the solution, and save your progress. Create a free account to unlock practice and keep track of your work.
Australian Mathematics Competition 2024 – Middle Primary (2024)
One puzzle per day. Cryptarithm, Magic Square, Summit. No sign-up required to play.
Play daily puzzle →Interactive problems and curated lessons—water pouring, magic squares, knight's tour, and more.
Browse library →See how you rank. Top solvers by problems solved correctly. Sign in to climb the ranks.
View leaderboard →Australian Mathematics Competition 2024 – Middle Primary (2024)