### Consecutive Numbers

An investigation involving adding and subtracting sets of consecutive numbers. Lots to find out, lots to explore.

### Calendar Capers

Choose any three by three square of dates on a calendar page...

### 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...

# What's on the Back?

##### Age 11 to 14 ShortChallenge Level

Four cards each have a number written on one side and a phrase written on the other. The four numbers are $2$, $5$, $7$ and $12$.
The four phrases are
Divisible by $7$
Odd
Prime
Greater than $100$

On each card, the number written does not have the property written on the other side of the card. What are the four number-property pairs?

If you liked this problem, here is an NRICH task that challenges you to use similar mathematical ideas.

This problem is taken from the UKMT Mathematical Challenges.
You can find more short problems, arranged by curriculum topic, in our short problems collection.