Maths Trick

Maths Trick 

Some Tips and Tricks

It is best to put the whole table into your memory using Math Trainer - Multiplication, but here are some tricks that may help you remember your times tables.

Everyone thinks differently, so just ignore any tricks that don't make sense to you.

The Best Trick

Every multiplication has a twin, which may be easier to remember.

For example if you forget 8×5, you might remember 5×8. This way, you only have to remember half the table.

Tricks by Number

to multiply by

Trick

2

add the number to itself (example 2×9 = 9+9)

5

the last digit goes 5, 0, 5, 0, ...

is always half of 10× (Example: 5x6 = half of 10x6 = half of 60 = 30)

is half the number times 10 (Example: 5x6 = 10x3 = 30)

6

if you multiply 6 by an even number, they both end in the same digit. 

Example: 6×2=12, 6×4=24, 6×6=36, etc

9

the last digit goes 9,8,7,6, ...

your hands can help! Example: to multiply 9 by 8,

hold your 8th finger down, and count "7" and "2",

the answer is 72

  is 10× the number minus the number. 

Example: 9×6 = 10×6 - 6 = 60-6 = 54

if you add the answer's digits together, you get 9. 

Example: 9×5=45 and 4+5=9. (But not with 9×11=99)

10

put a zero after it

11

up to 9x11: just repeat the digit (Example: 4x11 = 44)

  for 10x11 to 18x11: write the sum of the digits between the digits 

(Example: 15x11 = 1(1+5)5 = 165) 

Note: this works for any two-digit number, but if the 

sum of the digits is more than 9, you will have to

"carry the one" (Example: 75x11 = 7(7+5)5 = 7(12)5 = 825).

12

is 10× plus 2×

Remembering Squares Can Help

This may not work for you, but it worked for me. I like remembering the squares (where you multiply a number by itself):

1×1=1 2×2=4 3×3=9 4×4=16 5×5=25 6×6=36

   

7×7=49 8×8=64 9×9=81 10×10=100 11×11=121 12×12=144

And this gives me one more trick. if the numbers you are multiplying are separated by 2 (example 7 and 5), then multiply the number in the middle by itself and subtract one. See this:

5×5 = 25 is just one bigger than 6×4 = 24

6×6 = 36 is just one bigger than 7×5 = 35

7×7 = 49 is just one bigger than 8×6 = 48

8×8 = 64 is just one bigger than 9×7 = 63

etc ...