Answer:
The 80% confidence interval for the the population mean nitrate concentration is (0.144, 0.186).
Critical value t=1.318
Step-by-step explanation:
We have to calculate a 80% confidence interval for the mean.
The population standard deviation is not known, so we have to estimate it from the sample standard deviation and use a t-students distribution to calculate the critical value.
The sample mean is M=0.165.
The sample size is N=25.
When σ is not known, s divided by the square root of N is used as an estimate of σM:

The degrees of freedom for this sample size are:

The t-value for a 80% confidence interval and 24 degrees of freedom is t=1.318.
The margin of error (MOE) can be calculated as:
Then, the lower and upper bounds of the confidence interval are:

The 80% confidence interval for the population mean nitrate concentration is (0.144, 0.186).
Answer: 2 x -1 = -2. -2 + 2 =0
Answer:
The Chef will prepare 320 soups for a large banquet
Step-by-step explanation:
chef thinks that 2 out of every 5 dinner guests will order soup
===> Order soup / total number of attender
= 2/5
Total guest = 800 ==> 4 people ordered soup is
2 /5 = x /800
cross multiplying
x = 2 x 800 / 5
= 320
The Chef will prepare 320 soups for a large banquet
Answer:
n
b = ---------
(g+l)
Step-by-step explanation:
We need to isolate b. Starting from (g+l)b=n, we divide both sides by (g+l), obtaining
n
b = ---------
(g+l)
Answer:
B, False,
Step-by-step explanation: