MCQ
In Fig , $a+b=$
Image
  • A
    $117^{\circ}$
  • B
    $130^{\circ}$
  • C
    $127^{\circ}$
  • D
    $158^{\circ}$

Answer

C. $127^{\circ}$
 Since $A R B$ is a straight line.
$
\begin{array}{ll}
\therefore & \frac{x}{2}+5\left(\frac{x}{2}-1^{\circ}\right)+x+90^{\circ}=180^{\circ} \\
\Rightarrow & 4 x+4^{\circ}=180^{\circ} \Rightarrow 4 x=176^{\circ} \Rightarrow x=44^{\circ}
\end{array}
$
Using exterior angle property in $P Q R$, we obtain$
\begin{aligned}
& \angle Q R C=a+b \\
\Rightarrow \quad & \frac{x}{2}+5\left(\frac{x}{2}-1^{\circ}\right)=a+b \Rightarrow a+b=3 x-5^{\circ} \Rightarrow a+b=3 \times 44^{\circ}-5=127^{\circ}
\end{aligned}
$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free