Question

If the sum of three consecutive integers is $21$, then the sum of the two smaller integers is

• A. $11$
• B. $5$
• C. $12$
• D. $13$

Answer 1

The correct option is D $13$

Let the three consecutive number is $x,x+1,x+2$

$x+x+1+x+2=21$

$\Rightarrow 3x+3=21$

$\Rightarrow 3x=21-3$

$\Rightarrow 3x=18$

$\Rightarrow x=6$

Now,

$x=6$

$x+1=7$

So,

Sum of two smaller consecutive number is $x+x+1=6+7=13$

Hence, this is the answer.