Suppose a set of test scores is appproximately bell-shaped, with a mean of 68 and a range of 54. (a) The minimum test score is approximately , and the maximum test score is approximately . (b) The standard deviation of the test scores is approximately g

a.) Minimum test score = 41

    Maximum test score = 95

b.)An approximate value of the standard deviation is 9.

Step-by-step explanation:

The given set of test scores is approximately bell shaped.

The mean of the test scores, = 68

The range of the data set = 54.

a.) i.) Minimum test score  =

   ii.) The maximum test score =

b.) From the 68-95-99.7 rule, also known as the Empirical rule, tell us that an approximation of the range is 3 standard deviations either way from the mean. So from this rule we can say that the minimum can also be found from and the maximum can also be approximated as .

From the above we can say that the range can be written as

∴  

∴    

Therefore an approximate value of the standard deviation is 9.

30 miles

step-by-step explanation:

we know that 60 seconds equals 1 minute and 60 minutes 1 hour

44 ft       60 sec     60 min     158400   ft

  *   *   =

1 sec       1 min       1 hour         hour

we know that there are 5280 ft per mile

158400   ft       1 mile         30 miles

  *   =

1   hour               5280 ft     1 hour

so in 1 hour   it can travel 30 miles

x=half

step-by-step explanation: