Multiply by 5
Times 10, then halve it. 48 × 5 = 480 ÷ 2 = 240.
How long?
Type the answer. Correct answers move on by themselves. Press Enter to skip a wrong one.
How the trick works
- Multiply the number by 10 by adding a zero.
- Halve the result.
Worked examples
48 × 5: first 48 × 10 = 480.
Then halve it: 480 ÷ 2 = 240.
36 × 5: first 36 × 10 = 360.
Then halve it: 360 ÷ 2 = 180.
124 × 5: first 124 × 10 = 1240.
Then halve it: 1240 ÷ 2 = 620.
Practise it
Take the 1 minute drill above a few times. When you can do most of them without slowing down, try level 2, which mixes this trick with others.