Even though we are using variables, we still know that "difference" means subtraction. So, if the larger is x1 and x2, those variables go first. The smaller, y1 and y2 will go second. So our problem will look like this:
The diameter of the sphere is 60 mm which means its radius is 30mm. <span>The radius of a sphere is increasing at a rate of 5 mm/s. The formula for the radius when the time is x second would be: </span>r(t)<span>= 30+ 5x dr/dt= 5
The speed of </span><span>volume increase </span><span>of the sphere volume would be derived from sphere volume: </span>V(r)=4/3* pi * r^3<span> dV/dt= 4/3 * pi * 3r^2 * (dr/dt) =4/3* pi * 3(30)^2 * 5 = 18000 pi= 56571 mm^3/s</span>
