Question

If sum of three consecutive numbers is 18, then the smallest number is.

• A. 6
• B. 5
• C. 7

Answer 1

The correct option is B 5

Let the smallest number is $x$.
So, other two numbers are, $x+1$ and $x+2$.
Sum of these three numbers are $x+(x+1)+(x+2)$ which is equal to 18.
$\Rightarrow x+(x+1)+(x+2)=18\Rightarrow 3x+3=18\Rightarrow 3x=18-3\Rightarrow 3x=15\Rightarrow x=\frac{15}{3}\Rightarrow x=5$
Thus, the smallest number is 5.