What is the unit number in 111

How to multiply any number by a two-digit number (with step-by-step instructions)

How to Multiply Any Number by a Two-Digit Number (With Step By Step Instructions)!

Example.1 Solve

1) 12 x 13 =?

(2) 17 × 18 =?

(3) 87 x 92 =?

Solution: (1) 12 x 13 =?

Step I.

Multiply the right digits of the multiplicand and multiplier (unit number of the multiplicand by the unit number of the multiplier).

Step II.

Now do the cross multiplication, i.e. multiply 3 by 1 and 1 by 2. Add the two products and make a note to the left of 6.

Step III.

In the last step we multiply the left numbers of both the multiplicand and the multiplier.


Repeat the cross multiplication until all consecutive pairs of digits are exhausted. In Step II we crossed 25 and 17 and in Step III we crossed 32 and 17.

Or we can write the answer directly without writing the intermediate steps. The only thing we should pay attention to are the “supporting numbers”.


You should try direct calculation for this. That saves a lot of time. It is a very systematic calculation and is easy to remember. Watch the above steps over and over until you get this systematic cross-multiplication pattern.