Multiplication Tricks

 1) Multiplication with 11

23 X 11= 253

2___3

253 (2+3=5)

623 X 11= 6853

6_____3

6____53 (2+3= 5)

6853 (6+2= 8)

You can see multiplication can be done quickly by starting with the first and last digit as they remain the same unless there is a carry. Then insert the sum of adjacent digits in sequence between first and last digit.

Remember to carry if necessary. For example

98 X 11= 1078

9____8

9__78 (9+8=17  carry 1)

1078 (9+ carry 1)

469 X 11= 5159

4_____9

4____59 (6+9=15  carry 1)

4___159 (6+4+carry 1=11  carry 1)

5159 (4+ carry 1=5)

2) Multiplication with 5

When you multiply any number with 5, First multiply that number by 10 then divide by 2.

For example:

49 X 5=

49 X 10=490

490/2 = 245

3) Multiplication with 25

When you multiply any number with 25, First multiply that number by 100, then divide by 4.

For example:

68 X 25=

68 X 100= 6800

6800/4= 1700

4) Multiplication with 125

When you multiply any number with 125, First multiply that number by 1000, then divide by 8.

For example:

72 X 125=

72 X 1000= 72000

72000/8= 9000

5) Multiplication with 15

When you multiply any number with 15, First divide that number by 2, then add the value in the number itself. Lastly,  multiply the value by 10.

For example:

140 X 15=

140/2 = 70

70+140= 210

210 X 10= 2100

Thanks for reading!