Question

You have two spheres. Sphere a has radius ra and sphere b has radius rb = kra. What is b's volumevb intermsofva andk? Vb = va

Answer 1

$V_a=\dfrac{4}{3}\pi r_a^3\\\\V_b=\dfrac{4}{3}\pi r_b^3\\\\V_b=\dfrac{4}{3}\pi(kr_a)^3\qquad\text{substitute for r_b }\\\\V_b=k^3V_a$