Two rules:
Multiple of N (+/-) another Multiple of N = Multiple of N
Multiple of N (+/-) NON-Multiple of N = will always be a NON-Multiple of N
X divided by 6 leaves a remainder of 4
X/6 = a + (4/6)
X = 6(a) + 4
Where a = non-negative integer quotient
6(a), regardless of the value or a, will be a Multiple of 3
4 is NOT a Multiple of 3
X = the addition of a Multiple of 3 and a NON Multiple of 3
Thus X can never be divisible by 3
Logically:
We can think of X as the following
There is some unknown A value of balls on the floor. We are able to break up those A balls into groups of 6 ———-> with 4 balls left over
For every one of the A groups of 6 balls, we can sub-divide those groups into two groups of 3 balls each
However, the 4 balls that remain, there will always be 1 left over when we try to create another group of 3 balls
(B)
X/3 can never be an integer
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