Suppose that the weights of the basketball players of a tournament are approximately normally distributed with a mean of 190lb and a standard deviation of 15lb. Which of the following is a good approximation of the probability that a randomly selected player weighs more than 220lb?a. 1%b. 2.5%c. 5%d. 16%

b. 2.5%

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean and standard deviation , the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this problem, we have that:

Which of the following is a good approximation of the probability that a randomly selected player weighs more than 220lb?

This is 1 subtracted by the pvalue of Z when X = 220. So

has a pvalue of 0.9772

1 - 0.9772 = 0.0228

Close to 2.5%

So the correct answer is:

b. 2.5%

since your problem is x^4 = 81, what you have to undeo is the "to the fourth power" part.

the inverse (opposite operation) of "to the fourth power" is "to the fourth root".

  (x^4) ^ ¼   = 81 ^ ¼  

  81 = 3^4     so (3 ^ 4) ^ ¼   =   3 ^ 1   = 3

by hand: (3 ^ 4) ^ ¼   =   3 ^ (4 x ¼) = 3 ^ 1   = 3   (when you take a power to a power, multiply the exponents.)

or, do it by calculator. one way of finding the fourth root is to use ^ (1/4)

step-by-step explanation: