To check if a number $day is divisible by divisor(3), use the modulus operator, %:

If the number divisible by 3 then the modulus will return remainder 0, so the if condition will fail so add your logic in else condition.

if ($day % 3) { 
  # does not divide cleanly 
} 
else {
 # does. 
}

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(OR)

Even you can use the same as your if(($day%3) == 0) condition of checking the reminder is equal to 0. In this case you can add your logic in if(..) itself

All is well

In reply to Re: modulus question by vinoth.ree
in thread modulus question by healingtao

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