You may also like

problem icon

Consecutive Numbers

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

problem icon

I'm Eight

Find a great variety of ways of asking questions which make 8.

problem icon

Calendar Capers

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

Debt Recovery

Stage: 3 Short Challenge Level: Challenge Level:1

Tina gives Tony 70p.

Let $x$ be the amount Tony owes Tina (which will be negative if Tina owes Tony).
Tony owes Tina 40p: $x=40$.
Tina borrows 50p from Tony: $x=-10$
Tony gives Tina 60p: $x=-70$.
So Tina owes Tony 70p.

This problem is taken from the UKMT Mathematical Challenges.
View the archive of all weekly problems grouped by curriculum topic