The average of five consecutive even numbers, p, q, r, s and t is 40. What is the product of 'r' and 's' ?

• A. 1580
• B. 1680
• C. 1780
• D. 1480

Answer: (B)

Let the numbers be x, x + 2, x + 4, x + 6, and x + 8Avg = x + x + 2 + x + 4 + x + 6 + x + 8/5 = 40Therefore, 5x + 20 = 200Therefore, x = 180/5 = 36Therefore, r = x + 4 = 40                                 s =  x + 6 = 42Therefore, Product = 1680