Question

The average of $7$ consecutive numbers is $20$. What is the largest number?

• A. $23$
• B. $45$
• C. $15$
• D. $12$

Answer 1

The correct option is A $23$

Let $x$ be the smallest number.

Then according to the given conditions,

$\frac{x+x+1+x+2+x+3+x+4+x+5+x+6}{7}=20⟹\frac{7x+21}{7}=20$

$\therefore x+3=20⟹x=17$

Largest number is $x+6=23$