Children are often asked in tests to find fractions of numbers, such as, what is 3/8 of 24? 5/6 of 42? etc. It is a topic which they seem to struggle with, as they find it hard to visualise the problem, but if a child can visualise a problem they are much more likely to be able to solve it.

I thus explain to children that fractions of numbers has a lot to do with either cake, or chocolate bars (two of my favoutire things). If you wanted to find 3/8 of a chocolate bar the first thing that you would have to do is break up the chocolate bar, or divide it, into 8 equal pieces. You would then take 3 lots of these pieces. Similarly if you wanted to find 5/6 of a cake you would cut, or divide, the cake into 6 pieces and then take 5 lots of the pieces.

Therefore if you wanted to find 3/8 of 24 you would do exactly the same. You would firstly divide the number 24 into 8 equal pieces (each piece being worth 3 because 24 divided by 8 is 3) and then take 3 lots of these pieces (3 x 3 = 9) so 3/8 of 24 is 9.

Similarly to find 5/6 of 42 you would divide 42 into 6 equal pieces (each piece being worth 7) and then take 5 lots of these pieces (5 x 7 = 35). Thus 5/6 of 42 = 35.

I find it a lot easier if the children draw diagrams to help them visualise what is happening, although after a lot of practice and examples they should notice the pattern that they are always dividing the number by the denominator (bottom number) and multiplying the answer to this division sum by the numerator (top number). Hence the mantra DBMAT - Divide by the Bottom and Multiply the Answer by the Top.

Below I have put two worksheets which may be downloaded in order to practise finding fractions of numbers. The first download gives visual clues, whereas the second relies on the children being able to calculate them. As always both sheets have one page with questions completed followed by a blank on which different numbers can be added, so that your child can have plenty of practise. Although the lines on the first document look odd, they do seem to print out fine.

Download microsoft_word_visual_fractions_of_numbers.pdf

Download microsoft_word_calculating_fractions_of_numbers..pdf

It was fun and helped me!!

Posted by: Sean | 11/26/2007 at 08:34 PM