Both circle q and circle r have a central angle measuring 110°. the area of circle q's sector is 4π cm2, and the area of circle r's sector is 9π cm2. the radius of circle q is 7 cm. which is the radius of circle r?

We know that
When circles have the same central angle measure, the ratio of measure of the sectors is the same as the ratio of the radii squared.
so
rA²/rB²=A/B
where
rA> radius circle Q
rB> radius circle R
A> area sector Q
B> area sector R
rB²=B*rA²/A> 7²*[9π]/[4π]> 110.25> rB=√110.25
rB=10.5 cm

the answer is
radius of circle R is 10.5 cm

The correct answer is b