Answer:
(A) Yes, since the test statistic is in the rejection region defined by the critical value, reject the null. The claim is the alternative, so the claim is supported.
Step-by-step explanation:
Null hypothesis: The wait time before a call is answered by a service representative is 3.3 minutes.
Alternate hypothesis: The wait time before a call is answered by a service representative is less than 3.3 minutes.
Test statistic (t) = (sample mean - population mean) ÷ sd/√n
sample mean = 3.24 minutes
population mean = 3.3 minutes
sd = 0.4 minutes
n = 62
degree of freedom = n - 1 = 62 - 1 = 71
significance level = 0.08
t = (3.24 - 3.3) ÷ 0.4/√62 = -0.06 ÷ 005 = -1.2
The test is a one-tailed test. The critical value corresponding to 61 degrees of freedom and 0.08 significance level is 1.654
Conclusion:
Reject the null hypothesis because the test statistic -1.2 is in the rejection region of the critical value 1.654. The claim is contained in the alternative hypothesis, so it is supported.
Answer: 63/2π
Step-by-step explanation: C=πd
63=πd
D=63/π
r=1/2d
1/2×63/π=<u>63/2π</u>
There are 11 ways a pair of dice can show a 5. Of those, 2 have a sum of 6.
Your probability is 2/11.
Answer:
6852 feet .
Step-by-step explanation:
Refer the attached figure
The chairlift at a ski resort rises a total of 2600 feet from where it starts. i.e.AB = 2600 feet
The angle of elevation is about 22.3 degrees.i.e.∠ACB= 22.3°
We are supposed to find How far do riders travel on the lift i.e.AC
In ΔABC
We will use trigonometric ratio
So, riders travel 6852 feet .
Answer:
16.07 milligrams
Step-by-step explanation:
From the question,
Using the formula of radioactive decay,
R/R' = 2ᵃ/ᵇ..................... Equation 1
Where R = Original mass of the polonium-210, R' = Final mass of polonium-210 after decaying, a = Total disintegration time, b = half life of polonium-210.
Make R' the subject of the equation
R' = R/(2ᵃ/ᵇ)................ Equation 2
Given: R = 100 milligrams, a = 1 years = 365 days, b = 138.39 days
Substitute these values into equation 2
R' = 100/(2³⁶⁵⁰⁰/¹³⁸³⁹)
R' = 100/(6.222)
R' = 16.07 milligrams of plonium-210
