Multiplying by 9

Did you memorize your multiplication table? Forgot it?
You can use your fingers to calculate the result.
Hold your hands with palms facing you and assign the numbers 1 thought 10 to your fingers, starting with left pinky.

For example if you want to multiply  5 x 9, bend the fifth finger.  Number of fingers to the left of bent finger represent the tens, and the number of fingers to the right represent ones.  There are four fingers to the left and five fingers to the right, thus the solution is 45.

5 x 9 = 45

Would you like another example?  How about 7 x 9.
Bend the seventh finger.  You have six fingers to the right and three to the left.  The result is 63.

7 x 9 = 63

Now even if you forget the multiplication table you will be able to figure out at least how to multiply by 9.

Have fun playing with it.