Question

How much do wild mountain lions weigh? Adult wild mountain lions (18 months or older) captured and released for the first time in the San Andres Mountains gave the following weights (pounds):

70

110

128

129

60

64

Assume that the population of x values has an approximately normal distribution.

(a) Use a calculator with mean and sample standard deviation keys to find the sample mean weight x and sample standard deviation s. (Round your answers to one decimal place.)

x =	lb
s =	lb

(b) Find a 75% confidence interval for the population average weight μ of all adult mountain lions in the specified region. (Round your answers to one decimal place.)

lower limit	lb
upper limit	lb

Answer 1

SolutionA:

Use R software ..Use mean and std dev function in R .

wild_mountain_lions <- c(70,110,128,129,60,64)
mean(wild_mountain_lions)
sd(wild_mountain_lions)

output:

mean(wild_mountain_lions)
[1] 93.5
> sd(wild_mountain_lions)
[1] 32.45766

mean=x=93.5

standard deviation=s=32.5

Solutionb:

use t test function in R software

t.test(wild_mountain_lions,conf.level=0.75)

output:

One Sample t-test

data: wild_mountain_lions
t = 7.0562, df = 5, p-value = 0.0008836
alternative hypothesis: true mean is not equal to 0
75 percent confidence interval:
76.2614 110.7386
sample estimates:
mean of x
93.5

75% confidence interval for the population average weight μ of all adult mountain lions in the specified region

lower limit=76.3 lb

upper limit=110.7 lb