Multiplying with 9 and 99

We can simplify the multiplication of any number with 9. All we got to do is to multiply the number with 10 and then subtract the number itself.

Let?s take an example:

38 X 9 = (38 X 10) - 38 = 380 - 38 = 342

77 X 9 = (77 X 10) - 77 = 770 - 77 = 693

 

Multiplying with 99:

Expanding the logic of multiplying with 9, we can simplify multiplication of a number with 99.

We need to first multiply the number with 100 and then subtract the number itself.

Let?s do it with an example:

38 X 99 = (38 X 100) - 38 = 3800 - 38 = 3762

77 X 99 = (77 X 100) - 77 = 7700 - 77 = 7623