Answer:
86% or a difference of 743/3
Explanation:
The equation for a volume of a sphere is 4/3pi r^3 where r is the radius. Plugging in, we get 288pi for a radius of 6, and 121/3pi for a radius of 5.5. The ratio would be 288:121/3 without pi. Subtracting these two values we get 743/3 which is in simplest terms. As for the decrease in percentage, calculating the percentage of decrease would be the original value subtracted by the new value divided by the original value. This means 288 -121/3 is 743/3, and this divided by 288 is approximately 0.86. This means the percentage decrease is approximately 86% rounded to the nearest hundredths.