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There are **17** NRICH Mathematical resources connected to **Decimals**, you may find related items under Fractions, decimals, percentages, ratio and proportion.

Problem
Primary curriculum
Secondary curriculum
### Terminating or Not

Is there a quick way to work out whether a fraction terminates or recurs when you write it as a decimal?

Age 11 to 14

Challenge Level

Problem
Primary curriculum
Secondary curriculum
### Round the Dice Decimals 1

Use two dice to generate two numbers with one decimal place. What happens when you round these numbers to the nearest whole number?

Age 7 to 11

Challenge Level

Problem
Primary curriculum
Secondary curriculum
### Round the Dice Decimals 2

What happens when you round these numbers to the nearest whole number?

Age 7 to 11

Challenge Level

Game
Primary curriculum
Secondary curriculum
### Spiralling Decimals

Take turns to place a decimal number on the spiral. Can you get three consecutive numbers?

Age 7 to 14

Challenge Level

Problem
Primary curriculum
Secondary curriculum
### Doughnut Percents

A task involving the equivalence between fractions, percentages and decimals which depends on members of the group noticing the needs of others and responding.

Age 7 to 14

Challenge Level

Problem
Primary curriculum
Secondary curriculum
### Route Product

Find the product of the numbers on the routes from A to B. Which route has the smallest product? Which the largest?

Age 7 to 11

Challenge Level

Problem
Primary curriculum
Secondary curriculum
### 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 รท 360. How did this help?

Age 11 to 14

Challenge Level

Problem
Primary curriculum
Secondary curriculum
### Tiny Nines

What do you notice about these families of recurring decimals?

Age 14 to 16

Challenge Level

Problem
Primary curriculum
Secondary curriculum
### Matching Fractions, Decimals and Percentages

Can you match pairs of fractions, decimals and percentages, and beat your previous scores?

Age 7 to 14

Challenge Level

Problem
Primary curriculum
Secondary curriculum
### Shopping Basket

The items in the shopping basket add and multiply to give the same amount. What could their prices be?

Age 11 to 16

Challenge Level

Problem
Primary curriculum
Secondary curriculum
### Forgot the Numbers

On my calculator I divided one whole number by another whole number and got the answer 3.125. If the numbers are both under 50, what are they?

Age 7 to 11

Challenge Level

Problem
Primary curriculum
Secondary curriculum
### 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?

Age 11 to 14

Challenge Level

Problem
Primary curriculum
Secondary curriculum
### Reductant Ratios

What does the empirical formula of this mixture of iron oxides tell you about its consituents?

Age 16 to 18

Challenge Level

Problem
Primary curriculum
Secondary curriculum
### A Long Time at the Till

Try to solve this very difficult problem and then study our two suggested solutions. How would you use your knowledge to try to solve variants on the original problem?

Age 14 to 18

Challenge Level

Problem
Primary curriculum
Secondary curriculum
### Magic Matrix

Find out why these matrices are magic. Can you work out how they were made? Can you make your own Magic Matrix?

Age 7 to 11

Challenge Level

Problem
Primary curriculum
Secondary curriculum
### Decimal Time

Use the clocks to investigate French decimal time in this problem. Can you see how this time system worked?

Age 11 to 14

Challenge Level