Question

If pqr = 1 , rst = 0 , and spr = 0, which of the following must be zero?

AP
BQ
CR
DS
ET

Answer 1

DS will be zero

Explanation:

Checking through the examples given, it can be ascertained that S is the only letter present in all the equations that their products equal to zero.

So if it's also paired with D, the answer will also be zero.