how much do wild mountain lions weigh Adult wild mountain li

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):

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.)

91.5

s=30.2

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

I was able to figure A out but I can\'t understand how to calculate b.

Solution

b)

Note that              
              
Lower Bound = X - t(alpha/2) * s / sqrt(n)              
Upper Bound = X + t(alpha/2) * s / sqrt(n)              
              
where              
alpha/2 = (1 - confidence level)/2 =    0.125          
X = sample mean =    91.5          
t(alpha/2) = critical t for the confidence interval =    1.300949037          
s = sample standard deviation =    30.21092518          
n = sample size =    6          
df = n - 1 =    5          
Thus,              
              
Lower bound =    75.45466887          
Upper bound =    107.5453311          
              
Thus, the confidence interval is              
              
(   75.45466887   ,   107.5453311   ) [ANSWER]