# Divisibility, HCF & LCM Tricks and Formulas

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## Divisibility Tests

A number is divisible by 2, if its unit’s place digit is 0, 2, 4, or 8

A number is divisible by 3, if the sum of its digits is divisible by 3

A number is divisible by 4, if the number for med by its last two digits is divisible by 4

A number is divisible by 8, if the number formed by its last three digits is divisible by 8

A number is divisible by 9, if the sum of its digits is divisible by 9

A number is divisible by 11, if, starting from the RHS, (Sum of its digits at the odd place) – (Sum of its digits at even place) is equal to 0 or 11x

## HCF and LCM

## Application of H.C.F

The greatest natural number that will divide *x*, *y* and *z* leaving remainders *r*1, *r*2 and *r*3, respectively, is the

## Application of L.C.M

The smallest natural number that is divisible by *x*, *y* and *z* leaving the same remainder *r* in each case is the