n × 50
The trick, step by step
Multiply by 100: 68 × 100 = 6800.
Halve it: half of 6800 is 3400.
So 68 × 50 = 3400.
given working answer taken away
Why it works
50 is half of 100, so n × 50 = n × 100 ÷ 2.
Practise this trickTricks · Multiplying
Multiply by 50
Any number times 50, such as 68 × 50.