ABC26GN4543 · Area

Subject: General Aptitude · Chapter: Area · Exam: · Marks: · Difficulty:

The circumferences of two circles are 132 metres and 176 metres respectively. What is the difference between the area of the larger circle and the smaller circle?

(a)1048 sq. m

(b)1076 sq. m

(c)1078 sq. m

(d)1090 sq. m

(e)None of these

Answer

Answer (as printed): C

Explanation

$2 \pi R_{1}=132 \Rightarrow R_{1}=\frac{132 \times 7}{2 \times 22}=21 \mathrm{m}$. $$2 \pi R_{2}=176 \Rightarrow R_{2}=\frac{176 \times 7}{2 \times 22}=28 \mathrm{m} .$$ $$\begin{aligned} \therefore \text { Required difference } & =\pi\left(R_{2}^{2}-R_{1}^{2}\right)=\pi\left(R_{2}+R_{1}\right)\left(R_{2}-R_{1}\right) \\ & =\left(\frac{22}{7} \times 49 \times 7\right) \mathrm{m}^{2}=1078 \mathrm{m}^{2} . \end{aligned}$$

Open in whiteboard · Browse this chapter in the app