## Mental Arithmetic

having a feel for the numbers

600 times 0.3 140 times 80

decimals

**Example** A full railway ticket costs £ 24.90

If a student can claim a third off, how much do they pay?

*A third of 24.90 is 8.30.*

*
Subtract 8.30 from 24.90 to get 16.60.
*

Use this method only if you are absolutely sure that you have the right answer. Otherwise you would obviously lose out on the chance of getting consolation marks for method.