Date: Bell:
Unit 9: Statistics & SOL Review
Homework 2: Normal Distribution
& Z-Scores
** This is a 2-page document! **
1. The scores from a statistics test were {99, 60, 82, 78, 93, 71, 68, 86, 80, 95, 72, 64)
(a) Calculate the mean and standard deviation for the class.
HL=
(b) Draw and label the normal distribution curve.
(c) 68% of the students have a test score between
and
(d) 95% of the students have a test score between
and
(e) What percentage of the students scored less than a 79?
(1) What percent of the students scored between a 55 and 91

Data for the height of a model rocket launch in the air over time are shown in the table. darryl predicted that the height of the rocket at 8 seconds would be about 93 meters. did darryl make a good prediction? yes, the data are best modeled by a quadratic function. the value of the function at 8 seconds is about 93 meters. yes, the data are best modeled by a linear function. the first differences are constant, so about 93 meters at 8 seconds is reasonable. no, the data are exponential. a better prediction is 150 meters. no, the data are best modeled by a cubic function. a better prediction is 100 meters.