5 terms

How do you know if a number is divisible by 3?

sum of digits divisible by 3

how do you know if a number is divisble by four

last two digits are div by 4

how do you know if a number is divisible by six

even and divisble by three

how do you know if a number is divisbile by 9

sum of digits are divisible by 9

what is the work formula

(x*y)/(x+y)