Question

How can you find 5% of any number using mental math?

Answer 1

Answer:

Step-by-step explanation:

I'm not sure my way is going to be any quicker or better. Let's take an example.

Suppose you start with 456

Put a decimal at the end of the 6.   You get 456.

Shift the decimal to the left one place           45.6

Divide by 2

22.8 (done mentally)

Note: dividing by 2 is easier than dividing by 5. Or multiplying by 5 for that matter.

Check the result.

456 * 5/100 =2280 / 100.

Shift a decimal 2 places to the left.

22.80 which agrees with your result.

Answer 2

Just take 10% of the number and divide that by 2. Taking 10% of a number is easy, for example, 10% of 100 is 10, 10% of 45 is 4.5 - you simply move the decimal point over 1. Once you take the 10% just divide it by two and you get 5%.