Multiple choice general knowledge math & puzzles

The avg. of 11 results is 30, that of the first five is 25 and that of the last five is 28. Find the value of sixth number?

  1. 65

  2. 66

  3. 67

  4. 68

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Total of 11 results = 11×30 = 330. First five total = 5×25 = 125. Last five total = 5×28 = 140. Sum of first five + last five = 265. Sixth number = 330 - 265 = 65.