When multiplying a number by 10, move the decimal to the right. when multiplying a number by 0.1, move the decimal to the left. why?

When multiplying a number by 10, move the decimal to the right. Whenever a number is multiplied by 10, the decimal is shifted to one place in the right.

Like :

When multiplying a number by 0.1, move the decimal to the left. This means the number is multiplied by or we can say the number is simply divided by 10.

So, when a number is divided by 10, the decimal is shifted to one place on the left.

Like :

or

The reasons are:

The product of two numbers is represented as:

a * b

Assume that:

a = 5.73 and b = 10.

The expression becomes

5.73 * 10 = 57.3

Notice that, the decimal moved from the ten place to the hundred place after the numbers are multiplied.

This implies a product of 10

However, assume b = 0.1

The expression becomes

5.73 * 0.1 = 0.573

Notice that, the decimal moved from the ten place to the tenth place after the numbers are multiplied.

This implies a division by 10

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