1: ADDITION OF 5
* when adding number greater than 5 its easier to first substract 5 and add 10
Eg: 8+5=13
Also
8-5=3 then plus 10
3+10=13
Eg: 27+5=32
Also
27-5=22
22+10=32
2:SUBSTRACTION OF 5
*when substract any number with ending digit less than 5
Simply add 5 and substract 10
Eg: 42-5=37
Also 42+5=47
47-10=37
Eg: 71-5=66
Also
71+5=76
76-10=66
3:MULTIPLY 5 TIMES ANY NUMBER
(a) BY EVEN NUMBER
simply take a number to be multiplied cut it into half and add ZERO INFRONT
Eg: 5x42
42/2=21
21 add 0= 220
Eg:5x32
Simply
32/2=16
16 add 0= 160
(b) BY ODD NUMBER
its bit different but simply substract 1 from a number being multiplied by 5 cut it into half and make 5 to it as last digit
Eg: 5x3
Simply take 3-1=2
2/2=1
Then 1 and 5 = 15
5x3=15
Eg:5x9
Simply
9-1=8
8/2=4
4&5=45
5x9=45
4:DIVISION BY 5
Simply multiply by 2 and divide by 10
Eg: 1250/5
1250x2=2500 then divide by 10
2500/10=250
Eg: 256/5
512/10=51.2
5:SQUARE A TWO DIGIT NUMBER END WITH 5
*smply multiply the first digit by iself plus one and put 25 at end
Eg: 25x25
[2x(2+1)] & 25
6&25=625
Eg: 95x95
9(9+1) & 25
90 & 25=9025
6: *THINK OF BIG number *Bouble it
*Add 10
*halve it
*Take away your original number
THE ANSWER IS 5
Thanks for reading remember to come back for more math funny
Sweety
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