Conversion 1 - Decimals and fractions
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Convert Fractions to Decimals
There are two possible ways to do the conversion. The first method can be used as
long as you are able to spot the factors of 10, 100, 1000 in the denominators. The
second method applies to all fractions.
Method 1 – Using factors of 10, 100, 1000
7 7 4
25 25 4
1. Find the equivalent fraction with the
denominator of 10,100,1000, etc
28
(i.e. 28 100 ) 2. Move the decimal point to the left, the number
100
of times depending on the number of zero.
= 0.28
Factors of 10,100 and 1000
10 100 1000
1 x 10 1 x 100 1 x 1000
2x5 2 x 50 2 x 500
4 x 25 4 x 250
5 x 20 5 x 200
10 x 10 8 x 125
10 x 100
More working examples using method 1.
5 7125 4 4 2 7 7 5
8 8 125 5 5 2 20 20 5
625 8 35
1000 10 100
0.625 0.8 0.35
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Conversion 1 - Decimals and fractions
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Method 2 – Long Division
7 0.28
25
Long division steps:
1. 25 can’t go into 7, add a zero and a
2 decimal point after 7
2. Bring the decimal point up and add a
zero in front of the decimal point.
3. Divide 70 by 25, 2 remaining 20.
4. Add another zero and bring it down to
3 make the remainder to 200.
5. Divide 200 by 25, which is 8.
6. Answer is 0.28
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Conversion 1 - Decimals and fractions
____________________________________________________________________
Convert decimals to fractions
You first need to recognise the place value of the decimal before converting to
appropriate fractions:
1) Decimal reading:
0.1 This reads as 1 tenth (one decimal place)
0.14 This reads as 14 hundredths (two decimal places)
0.234 This reads as 234 thousandths (three decimal places)
2) Converting to fractions:
x x x
Tenth Hundredths Thousandths
10 100 1000
Working Example:
4
0.4
10 1. Read the decimal mentally
4 2 (I.e. read as 4 tenths)
10 2
2 2. Write the fraction based on the reading
5
3. Reduce the fraction to its lowest term.
Revision Exercise
Change the following fractions to decimal.
1 2 66 382 27
1) 2) 3) 4) 5)
4 8 19 100 25
11 3 6 14 923
6) 7) 8) 6 9) 1 10 3
50 10 9 25 1000
Convert decimal to fraction
1) 0.83 2) 0.19 3) 0.35 4) 1.325 5) 3.03
6) 2.25 7) 5.52 8) 4.90 9) 8.5 10 9.11
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