Question

The population parameters below describe the full-time equivalent number of students (FTES) each year at Lake Tahoe Community College from 1976–1977 through 2004–2005. μ = 1000 FTES median = 1,014 FTES σ = 474 FTES first quartile = 528.5 FTES third quartile = 1,447.5 FTES n = 29 years

a. 75% of all years have an FTES at or below__ .

b. 75% of all years have an FTES at or above __ .

c. The population standard deviation is __ FTES.

d. What percent of the FTES were from 528.5 to 1447.5? __%

f. How many standard deviations away from the mean is the median? Round to two decimal places.

I know you only are required to answer one, but if you know how to do the rest I could really use your help.

Answer 1

Sol)

Given

Mean = 1000

S.D = 474

Median = 1014

Q1 = 528.5

Q3 = 1447.5

N = 29

a)

75% of all years have an FTES at or below

The answer is third quartile

Q3 = 1447.5

b)

75% of all years have an FTES at or above

The answer is first quartile

Q1 = 528.5

c)

Population standard deviation is

S.D = 474

d)

What percent of FTES are from 528.5 to 1447.5

528.5 is the first quartile = 25%

1447.5 is the thirsmd quartile = 75%

= 75 - 25

= 50%

50% of FTES were from 528.5 to 1447.5

f)

How many S.D's away from mean is median

Mean = 1000

Median = 1014

Mod = | mean - median |

= | 1000 - 1014 |

= | -14 |

= 14

x = 14 / 474 = 0.029

The median is 0.029 standard deviations away from the mean