Question

What is the arithmetic mean of the progression $11,22,33,44,55,66,77?$

• A. $44$
• B. $208$
• C. $308$
• D. $48$

Answer 1

The correct option is A $44$

Using the formula for required arithmetic mean $=\frac{\text{sum of the terms}}{\text{number of terms}}$

After substituing the values we get: $=\frac{11+22+33+44+55+66+77}{7}$

$=\frac{11(1+2+3+4+5+6+7)}{5}=\frac{11\cdot 28}{7}=11\cdot 4=44$