schoolash.blog - Children must have still felt the difficulty of memorizing basic multiplication which totals nearly 100.
There is a simple technique if oblivious to the basic multiplication.
Following methods:
Suppose we want to know what is the value of multiplying 7 x 8
Fill in the circle below the number 7 from the reduction of 10 -7 is 3. Fill in the circle below the number 8 from the reduction of 10-8 which is 2.
7 x 8 multiplication result can be searched in the following ways:
The first digit reductions obtained from 7 - the circle into two namely 7-2
or can be obtained from the first digit reduction in 8 - circle one that is 8-3
The results of both must be the same ie 5
The second digit multiplication value obtained from circle 1 to circle 2 is 3 x 2
So when combined with the first digit to 2 digits will be obtained 56
What about the above process?
Are you still confused?
Let's try again with some other multiplication eg 8 x 9
- We create 2 circles under the number 8 and 9
- We fill the first circle with a value of 10-8 = 2
- We fill the second circle with a value of 10-9 = 1
- We compute the first digit of the result of multiplication yait 8-1 or 9 -2 would obtained a score of 7
- We calculate the second digit of the theoretical value of loop 1 and loop 2 is 2x 1 = 2
the importance of the incorporation of 72 digit1 and digit2
so 8x9 = 72
Hopefully from the above two examples you can easily practice it
Development of methods
Multiplication 2 digit number near 100
The above method can be further developed to compute the fast multiplication of two digit numbers approaching 100.
eg 98 x 92
process such as the following:
- Create a circle under the 98 and 92
- The contents of the first circle = 100-98 = 2
- The contents of the second circle = 100-92 = 8
- Get the first 2 digits -> 98-8 = 90 or 92 -2
- 2 digits both acquired -> 8 x 2 = 16
So a 98 x 92 is 9016
looking for 97x97 multiplication results?
said:
- Create a circle under the 97 and 97
- The contents of the first circle = 100-97 = 3
- The contents of the second circle = 100-97 = 3
- Get the first 2 digits -> 97-3 = 94
- 2 digits both acquired -> 3 x 3 = 09 -> 9
then the value 97x97 is 9409
