Multiple choice general knowledge math & puzzles

Three people A,B,C weigh themselves in a particular order..First A,B,C weigh themselves and then AB,BC,CA and ABC together resptectively..The last measured weight is 180Kg..The average of 7 measures?

  1. 320

  2. 360/7

  3. 345

  4. 720/7

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

The last measure is A+B+C = 180. The 7 measures are A, B, C, A+B, B+C, C+A, and A+B+C. Summing these gives 4(A+B+C) = 4 * 180 = 720. The average of the 7 measures is therefore 720/7.