SOLUTION: The mean length of angelfish (a popular tropical fish for aquariums) is 9.6 cm with a standard deviation of 2 cm. Assuming that the length of angelfish is a normal random variable,

Algebra ->  Probability-and-statistics -> SOLUTION: The mean length of angelfish (a popular tropical fish for aquariums) is 9.6 cm with a standard deviation of 2 cm. Assuming that the length of angelfish is a normal random variable,      Log On


   



Question 1026014: The mean length of angelfish (a popular tropical fish for aquariums) is 9.6 cm with a standard deviation of 2 cm. Assuming that the length of angelfish is a normal random variable, find the probability that a randomly selected angelfish would be between 5.86 and 12.72 cm in length. Enter your answer as a decimal number correct to four decimal places.
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
z=(x-mean)/sd
so (5.86-9.6)/2=3.742=-1.87
(12.72-9.6)/2=3.12/2=1.56
we need the probability of -1.87 is less than z which is less than 1.56
That is 0.9099.
It makes sense because it is almost the difference between +/- 2 SD, which is 0.9544.