Basics of Simplification | Multiplication of Two Digits By Two Digits

To find product of two 2-digit numbers quickly, take a look at the following steps-

Step 1 :- Multiply both the unit place digits with each other.

Step 2 :- Cross Multiply and add both products.

Step  3 :- Multiply both the Ten's place digits with each other.

Note - You must make sure take carry if the result in each part exceeds 9 from right to left.

Let's look at some examples.

For Ex.  31 x 21

Step 1 :- Multiply both the unit place digits with each other (i.e. 1 x 1 = 1)

Step 2 :- Cross Multiply and add both products [i.e. (3 x 1) + (1 x 2) = 5].

Step  3 :- Multiply both the Ten's place digits with each other (i.e. 3 x 2 = 6) and add the '1' carried which results 7.

Final Result  :- 651.

For Ex.  43 x 12

Step 1 :- Multiply both the unit place digits with each other (i.e. 3 x 2 = 6)

Step 2 :- Cross Multiply and add both products [i.e. (4 x 2) + (3 x 1) = 11]. As this results exceeds 9, 1 will be carried.

Step  3 :- Multiply both the Ten's place digits with each other (i.e. 4 x 1 = 4) and add the '1' carried which results 5.

Final Result  :- 516.

For Ex.  53 x 27

Step 1 :- Multiply both the unit place digits with each other (i.e. 3 x 7 = 21) As this results exceeds 9, 2 will be carried.

Step 2 :- Cross Multiply and add both products [i.e. (5 x 7) + (3 x 2) = 41]. Add the '2' carried which results 43

As this results exceeds 9, 4 will be carried.

Step  3 :- Multiply both the Ten's place digits with each other (i.e. 5 x 2 = 10) and add the '4' carried which results 14.

Final Result  :- 1431.

For Ex.  64 x 39

Step 1 :- Multiply both the unit place digits with each other (i.e. 4 x 9 = 36) As this results exceeds 9, 3 will be carried.

Step 2 :- Cross Multiply and add both products [i.e. (6 x 9) + (4 x 3) = 66]. Add the '3' carried which results 69

As this results exceeds 9, 6 will be carried.

Step  3 :- Multiply both the Ten's place digits with each other (i.e. 6 x 3 = 18) and add the '6' carried which results 24.

Final Result  :- 2496.

For Ex.  78 x 83

Step 1 :- Multiply both the unit place digits with each other (i.e. 8 x 3 = 24) As this results exceeds 9, 2 will be carried.

Step 2 :- Cross Multiply and add both products [i.e. (7 x 3) + (8 x 8) = 85]. Add the '2' carried which results 87.

As this results exceeds 9, 8 will be carried.

Step  3 :- Multiply both the Ten's place digits with each other (i.e. 7 x 8 = 56) and add the '8' carried which results 64.

Final Result  :- 6474.

Problems For Practice 

1) 54 x 63

2) 32 x 49

3) 87 x 36

4) 16 x 91

5) 77 x 46

6) 28 x 65

7) 86 x 44

8) 33 x 53

9) 69 x 74

10) 78 x 83