Sunday, September 16, 2012

8x9 = 72, Hard? Here is a easy way to do it using fingers.

It is sometimes hard to do single digit multiplications when it get pass 5, 6. Here is a easy way to do single digit multiplications. It is very fast when you get use to it.

This is how we do it.

Problem: 7*8 = 56

1. touch figures with 7 and 8
2. number of fingers above that touching fingers gives you, your 'ones' value. Here is how we take it.
                no. of fingers above in left * no. of fingers above in right
                                      3           *                2                    =            6
3. number of all other fingers (including touching) gives you the tens value (here 5)
4. Using above two values you get your answer (5*10 + 6*1 = 56)

Below image will help you in understanding...

It is even harder than multiplying single digit numbers ? believe me it will look so simple when you use it few times.