The ratio of the radii is 2:1, so the ratio of their surface areas is 4:1. <span>The area of a sphere is defined by 4 * pi * r^2 </span>
<span>So if the radius of the first sphere is 2r, then it would be (2r)^2 = 4r^2 </span>
<span>The rest is the same. So the ratio of their surface areas would be </span>
<span>4 * pi * 4r^2 divided by </span>
<span>4 * pi * r^2 </span>
<span>or 4.</span>
Answer:
How are we supposed to solve this there is no image
Step-by-step explanation:
Answer:
b. 25%
Step-by-step explanation:
(new - old)/ old * 100%
150 - 120 = 30 ... 30/120 = .25 * 100% = 25%
Evaluate<span> the series by expanding the summation, then adding all of the values. 154 would be the answer.</span>