BACK TO WORKSHEETS
When we substitute a number for a letter, we simply replace the letter with the number.
However, we must remember that 4b means 4 x b.
Example
Work out the value of the following expression when a = 0.4
3a - 1
Answer
3a - 1
This means 3 x a - 1
Substitute 0.4 for the letter a:
3 x 0.4 - 1
Multiply first - remember the order of BIDMAS (or BODMAS)
1.2 - 1 = 0.2
It might look complicated, but you'll soon find it becomes second nature. Just work through it one step at a time.
Are you ready for some questions?
