Answer:
A t-score of 1.701 should be used to find the 95% confidence interval for the population mean
Step-by-step explanation:
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 29 - 1 = 28
Now, we have to find a value of T, which is found looking at the t table, with 28 degrees of freedom(y-axis) and a confidence level of 0.95(
). So we have T = 1.701.
A t-score of 1.701 should be used to find the 95% confidence interval for the population mean
200x 9, nine times two hundred,
Answer:
99.7%
Step-by-step explanation:
Using the z score formula
z-score is z = (x-μ)/σ
where:
x = raw score
μ = population mean
σ = population standard deviation.
a) for x = raw score = 35
μ = population mean = 44
σ = population standard deviation =3
z = (35 - 44)/3
z = -9/3
z = -3
b) for x = raw score = 53
μ = population mean = 44
σ = population standard deviation =3
z = (53 - 44)/3
z = 9/3
z = 3
We would use the standard normal distribution table to find their probabilities
P(Z<=-3)=0.0013499
P(Z<=+3)=0.99865
So P(-3<=Z<=3)=0.99865 - 0.0013499 = 0.9973
Converting to percentage = 0.9973 × 100 = 99.73%
Therefore, the percentage of auto batteries of this brand that have a life of 35 to 53 months to one decimal place is 99.7%
Answer:
-21
28
Step-by-step explanation:
1) if r = -4
Substitute r = -4 in 3r - 9
= 3 * (-4) - 9
= -12 - 9
= -21
2) ( 4 / 7 ) * x = 16
4 * x = 16 * 7
x = 4 * 7
x = 28
Answer:
eight
Step-by-step explanation:
