Question

The ratio of the area (in $cm^2$) to circumference (in cm) of a circle is 35 : 4. Find the circumference of the circle?

• A. 121 cm
• B. 154 cm
• C. 110 cm
• D. 132 cm

Answer 1

Answer:

C. 110 cm

Given:

The ratio of area (in cm²) to circumference (in cm) of a circle = 35 : 4

Formula Used:

Area of circle = πr²

The perimeter of circle = 2πr

Calculation:

Let the radius of the circle be ‘r’ cm

According to the question,

$\frac{πr^2}{2πr}=\frac{35}{4}$

⇒ $\frac{r}{2}=\frac{35}{4}$

⇒ r = 17.5 cm

∴ Circumference of the circle = $2\times{(\frac{22}{7})}\times{17.5}$ = 110 cm