DIVISIBILITY RULES
Here are Divisibility rules for your reference:
A number is divisible by
TWO: if last digit is 0, 2, 4, 6, or 8
THREE: if the sum of the digits is divisible by 3
FOUR : if the last two digits is divisible by 4
FIVE: if the last digit is 0 or 5
SIX: if the number is divisible by 2 and 3
SEVEN : Cross off the last digit - double this digit and subtract it from the number that remains. {If required, keep doing it till you get a small number.} If the number is divisible by 7, the original number is divisible by 7 .
This one's trick; so here's an example.
i) Consider: 2275
Last digit is 5 - double this i.e. 10. Subtract 10 from 227. Ans = 217
Now 217 is divisible by 7 - so 2275 is divisible by 7.
ii) Consider 15925
Last digit is 5 - double this i.e. 10. Subtract 10 from 1592. Ans = 1582
Last digit is 2 - double this i.e. 4. Subtract 4 from 158. Ans = 154
154 is divisible by 7 - so 15925 is divisible by 7.
EIGHT : if last 3 digits is divisible by 8
NINE: if the sum of the digits is divisible by 9
TEN: if the last digit is 0
ELEVEN: Subtract the last digit from the number formed by the remaining digits. If new number is divisible by 11, the original number is divisible by 11
TWELVE: if the number is divisible by 3 and 4
No comments:
Post a Comment