Equal arcs in two circles subtend angles $65^{\circ}$ and $110^{\circ}$ at the centres. The ratio of the radii $r_{1} : r_{2}$ is:
A$22 : 13$
B$13 : 22$
C$65 : 110$
D$110 : 65$
Answer & Solution
Correct answer: A. $22 : 13$
Equal arcs: $l = r_{1}\theta_{1} = r_{2}\theta_{2}$, so $\dfrac{r_{1}}{r_{2}} = \dfrac{\theta_{2}}{\theta_{1}} = \dfrac{110}{65} = \dfrac{22}{13}$.
Note the **inverse** relation: smaller angle ↔ larger radius (since the arc length is fixed).
Related questions
Penalty for wrong answers : THERE WILL BE PENALTY FOR WRONG ANSWERS MARKED BY A CANDIDATE Penalty for wrong answers : THERE WILL BE PENALTY FOR WRONG ANSWERS MARKED BY A CANDIDATE For [[1,2],[2,4]], the determinant equals:If A is invertible, |A^{−1}| equals:For a 3 × 3 non-singular A with |A| = 5, the value of |adj A| is:For a non-singular square matrix A of order n, |adj A| equals:For non-singular A, B of the same order, (AB)^{−1} equals:For a non-singular A, (A^{−1})^{−1} equals: