The average of 3 odd consecutive numbers is 15. What is the sum of first and last numbers?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 30
Consecutive odd numbers differ by 2, so three of them can be written as \(x\), \(x+2\), \(x+4\). In such an evenly spaced set, the average is the middle number.
Middle number \(=15\), so the numbers are 13, 15 and 17
First \(+\) last \(=13+17=30\)