The number of hours per day a college student spends on homework has a mean of 6 hours and a standard deviation of 1.25 hours. yesterday she spent 3 hours on homework. how many standard deviations from the mean is​ that? round your answer to two decimal places.

Three coins are flipped. what is the probability that there will be at least two tails?

Which expression is equivalent to 8(k + m) − 15(2k + 5m)?

Cor d? ? me ? max recorded the heights of 500 male humans. he found that the heights were normally distributed around a mean of 177 centimeters. which statements about max’s data must be true? a) the median of max’s data is 250 b) more than half of the data points max recorded were 177 centimeters. c) a data point chosen at random is as likely to be above the mean as it is to be below the mean. d) every height within three standard deviations of the mean is equally likely to be chosen if a data point is selected at random.