Mathematics
Medium
Question
The average of 9 observations was 9, that of the 1st of 5 being 10 and that of the last 5 being 8. What was the 5th observation?
A
9
✓ Official correct answer
B
8
C
7
D
6
Community credibility
Registered members can vote for the answer they believe is correct today and explain why. If the facts change after an election or news event, suggest a new option so others can vote it up.
A
9
No member explanations yet for this option.
B
8
No member explanations yet for this option.
C
7
No member explanations yet for this option.
D
6
No member explanations yet for this option.