The lifespans of gorillas in a particular zoo are normally distributed. The average gorilla lives 20.8 years; the standard deviation is 3.1 years. Use the empirical rule (68 – 95 - 99.7%) to estimate the probability of a gorilla living longer than 23.9 years.

Daniel bought a computer game for $25 and later sold it to thomas for a 40% profit. how much did daniel sell the computer game for?

The number if marbles of different colors stored in a hat is listed below: 4 red marbles 10 green marbles 7 blue marbles. without looking in the hat, dan takes out a marble at random. he replaces the marble and then takes out another marble from the hat. what is the probability that dan takes out a blue marble in both draws?

When i'm with my factor 5, my prodect is 20 .when i'm with my addend 6' my sum is 10.what number am i