Question

The mean of a certain number of observations is $35$. What is the new value of the mean if each observation is increased by $7$.

• A. $35$
• B. $40$
• C. $42$
• D. None of these

Answer 1

The correct option is C $42$

Mean of $n$ observations = $35$
Sum of $n$ observations = $35n$
If each observation is increased by $7$
New sum = $35n+7n=42n$
thus, new mean = $\frac{42n}{n}=42$