Statistics probability

Question

The average number of chocolate chips in one ounce is 57 with a standard deviation of 1.6. Find the probability that a randomly selected ounce of chocolate chips will contain between 54 and 59 chocolate chips

Answer 1

Assuming that this is a standard normal, bell-shaped distribution, the probability would be calculated either with the empirical rule (68, 95, 99.7) or with your calculator (hopefully a TI-84, or whatever works online).

Since this doesn't fit with the empirical rule, you'd have to calculate this using your TI-84 with the normal cdf command. The normal cdf command will calculate the probability of a random variable within a normal distribution with mean 0 and standard deviation of 1 (if not specified) falling within a certain range.

The normal cdf command on the TI-84 allows you to input four things in the following order: the lower bound of your range, upper bound of your range, the mean of your distribution, and the standard deviation. In this problem, you'd find the normal cdf command and enter "normalcdf(54, 59, 57, 1.6)." Hope that helps!