The sum of three consecutive odd numbers is 20 more than the first of these numbers.
The sum of three consecutive odd numbers is 20 more than the first of these numbers. What is the middle number?
Answer/Solution
9
Steps/Work
Sol.
Let the numbers be x, x + 2 and x + 4.
Then, x + (x + 2) + (x + 4) = x + 20 ⇔ 2x = 14 ⇔ x = 7.
∴ Middle number = x + 2 = 9.
Answer C
Let the numbers be x, x + 2 and x + 4.
Then, x + (x + 2) + (x + 4) = x + 20 ⇔ 2x = 14 ⇔ x = 7.
∴ Middle number = x + 2 = 9.
Answer C