#### You may also like

A mathematician goes into a supermarket and buys four items. Using a calculator she multiplies the cost instead of adding them. How can her answer be the same as the total at the till?

### Round and Round and Round

Where will the point stop after it has turned through 30 000 degrees? I took out my calculator and typed 30 000 ÷ 360. How did this help?

### Toad in the Hole

Is it cheaper to cook a meal from scratch or to buy a ready meal? What difference does the number of people you're cooking for make?

# Decimal Time

##### Stage: 3 Challenge Level:

This problem is designed to intrigue a little. To tackle the problem, pupils will need to be comfortable with manipulating fractions and decimals, and it would be a good idea to have calculators to hand.

It is an excellent way to highlight misconceptions associated with our digital clock, for example that 12.50 is not 0.5 hours after 12.00. It could be a good vehicle for investigating why our clock is based on the number 60 and researching calendar systems of ancient cultures.