Check out this challenging math exercise for GMAT. Try solving yourself before watching the solution! Apologies for small type face and poor resolution of the exercise image. I’ve repeated it just here:
PROBLEM: A store sells a certain product at a fixed price per unit. At the product’s current price, [q] units cost a total of exactly $300. If the price were lowered by $5 from its current value, then [q + 2n] units would cost exactly $300. If the price were raised by $5, then [q – n] units would cost exactly $300. What is the value of q?
ANSWER CHOICES:
A: 10, B: 15, C: 20, D: 25, E: 30
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