If a number is divisible by 2 and 4 then it is divisible by 8?
Not entirely. If the number is 4, then 4/2 = 2, and 4/4 = 1, but
dividing by 8 does not produce a whole number. 4/8 = .5 or 1/2.
This is not always true, but it can be true if the number is
something like 32, where 32/2 = 16, 32/4 = 8, and 32/8 = 4.