Question

The sum of three consecutive multiples of 5 is 285. Find the largest number.

• A. 75
• B. 100
• C. 90
• D. 120

Answer 1

Answer:

B. 100

Three consecutive numbers are x, x + 1 and x + 2 Three consecutive multiples of 5 are 5x, 5(x + 1) and 5(x + 2) The sum of three consecutive multiple of 5 is 285 5x + 5x + 5 + 5x + 10 = 285 ⇒ 15x = 270 ⇒ x = 18 Now, largest number = 5(x + 2) = 5 × 20 = 100