You may also like
Consecutive Numbers
An investigation involving adding and subtracting sets of consecutive numbers. Lots to find out, lots to explore.
Days and Dates
Investigate how you can work out what day of the week your birthday will be on next year, and the year after...
Age 11 to 14 Short
Challenge Level
Answer: 32
First round:
only even numbers leftSecond round:
only multiples of 4 leftThird round:
only multiples of 8 leftFourth round: Only multiples of 16 will be left
Fifth round: Only multiples of 32 will be left.
32 is the only multiple of 32 under 50, so 32 is the last number left.
This problem is taken from the UKMT Mathematical Challenges.
You can find more short problems, arranged by curriculum topic, in our short problems collection.
Copyright © 1997 - 2023. University of Cambridge.
All rights reserved.
NRICH is part of the family of activities in the Millennium Mathematics Project.
NRICH is part of the family of activities in the Millennium Mathematics Project.