-----ASIDE-----------------------
There's a nice rule that says, "If N divided by D equals Q with remainder R, then N = DQ + R"
For example, since 17 divided by 5 equals 3 with remainder 2, then we can write 17 = (5)(3) + 2
Likewise, since 53 divided by 10 equals 5 with remainder 3, then we can write 53 = (10)(5) + 3
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GIVEN: When Q is divided by W, the quotient is R and the remainder is E.
So, we can write: Q = WR + E

Which of the following expressions is equal to E?
Take: Q = WR + E
Subtract WR from both sides to get: Q - WR = E

Answer: C

Cheers,
Brent

When Q is divided by W, the quotient is R and the remainder is E

Theory: Dividend = Divisor*Quotient + Remainder

Q -> Dividend
W -> Divisor
R -> Quotient
E -> Remainder

=> Q = W*R + E = WR + E
=> E = Q - WR = Q - RW

So, Answer will be C
Hope it helps!

Watch the following video to learn the Basics of Remainders