21. MODELING WITH MATHEMATICS The value
mountain bike v (in dollars) can be approximated
the model v = 200(0.75), where t is the number of
vears since the bike was new. (See Example 2.)
a. Tell whether the model represents exponential
growth or exponential decay.
b. Identify the annual percent increase or decrease in
the value of the bike.
c. Estimate when the value of the bike will be $50.

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.

Select the two pairs of figures that are similar.

Astudent draws two parabolas both parabolas cross the x axis at (-4,0) and (6,0) the y intercept of the first parabolas is (0,-12). the y intercept of the second parabola is (0,-24) what is the positive difference between the a values for the two functions that describe the parabolas