Relate Fractions to Decimal Equivalents

In this activity, we will be learning to relate fractions to decimals.

We can convert this decimal to a fraction:

1.72 = ?

1.72  = one whole and 72 hundredths

1.72 =  1 and  72/100

We can also convert this fraction to a decimal:

2 and 45/100 = ?

We have 2 whole numbers.

We have 45 hundredths which can be written as 0.45

So, 2 and  45/100 =  2.45

Let's try some examples.

Example 1

Lucy writes a fraction as the decimal 0.2.

What fraction is Lucy thinking of?

Answer

The decimal 0.2 has a two in the tenths place.

There are no ones.

0.2 = 2/10 or two tenths

Example 2

Sam has eaten 37/100 of a pizza.

What is this as a decimal?

Answer

Sam hasn't eaten as much as a whole pizza (phew!) so there are no whole numbers.

He has eaten 37/100 which can be written as 0.37

So, Sam has eaten 0.37 of a pizza.

We may see some trickier fractions and decimals!

To convert a fraction to a decimal, we divide the numerator by the denominator. 

1/2 = 1 ÷ 2 = 0.5

Here are some common conversions you may want to write down. 

1/4 = 0.25

1/3 = 0.33

1/6 = 0.16

1/8 = 0.125

1/10 = 0.1

1 /5 = 0.2

Now it's time to try some questions yourself.