The average of first six multiples of 11 is:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → 38.5
The average is the sum divided by the number of values. The first six multiples of 11 are 11, 22, 33, 44, 55 and 66.
Sum \(=11\times(1+2+3+4+5+6)=11\times21=231\)
Average \(\displaystyle =\frac{231}{6}=38.5\)
Shortcut: The multiples go up by the same amount each time, so their average is the average of the first and last.
\(\displaystyle\frac{11+66}{2}=38.5\)