The mean of 5 numbers is 15. If one more number is included

The mean of 5 numbers is 15. If one more number is included, the mean of the 6 numbers becomes 17. What is the included number?

  1. 24
  2. 25
  3. 26
  4. 27

Answer

Sum of five numbers = Mean × Number of numbers

Sum of five numbers = 15 × 5 = 75

Now, sum of six numbers = 17 × 6 = 102

New number = 102 - 75 = 27

The correct option is D.