Question

If the arcs of same length in two circles subtend angles of $60^{\circ}$ and $75^{\circ}$ at their centers, then the ratio of their radii is

• A. $1: 3$
• B. $3: 8$
• C. $5: 4$
• D. $5: 3$

Answer 1

Answer: (C)

By using the formula $s=r \theta$
we conclude that
$\frac{r_{1}}{r_{2}}=\frac{\theta_{2}}{\theta_{3}}=\frac{75}{60}=\frac{5}{4}$.