First put the 20 fifths metres into something a little more recognisable: 20 x 1/5 metres This is also 20/5 metres And as 20/5 = 4, 20 fifths metres = 4 metres.
In each metre, there are 100 centimetres, so 4 metres to 100 centimetres = 4 x 100 = 400 centimetres
Start with the brackets. Then do 5 multiply 1 which is 5 then divide that 5 from 20 which gets you 4. Times the outside of the brackets with the inside which will give you the answer of 16
