Question

The mean of seven numbers is $63$. If the six number are$65,70,68,59,73,55$. Find the seventh number.

• A. $51$
• B. $52$
• C. $53$
• D. $54$

Answer 1

Answer: (A)

$51$

Mean or average is defined as the sum of all the observations divided by total number of observations.
Thus, $65+70+68+59+73+55+x=63\times 7$
$\Rightarrow 390+x=441$
$\Rightarrow x=51$