The mean of p, q, r, s and t is 280. If the mean of p, r and t is 240, what is the mean of q and s?

  1. A. 310
  2. B. 320
  3. C. 330
  4. D. 340

Correct Answer: D. 340

Explanation

The sum of the 5 numbers is 5 \times 280 = 1400. The sum of p, r, and t is 3 \times 240 = 720. Therefore, q+s = 1400 - 720 = 680. Their mean is \frac{680}{2} = 340.

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