Double digit Multiplication in single step
October 23, 2017
Multiplication of a two digit number by another two digit number in one step
To multiply a two digit number by another two digit number, we usually take three steps, two for multiplication and one for addition to get the final answer. But it is possible to multiply in one step.
Let us say we wish to multiply 45 by 67.
Step one: we multiply 5 by 7 and the answer is 35. We put 5 and carry over 3.
Step Two: we do cross multiplication here, 5 by 6 and 4 by 7. The results are 30 and 28. We add them. It is 58. We add this total to the number we carried in the previous step, in this case 3. The total now is 61. We write 1 and carry over 6.
Step Three: we multiply 4 and 6 and the result is 24. To this number we add the carry over number, in this case 6. The new total is now 30.
The final result is then 3015.
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