Answer:
(0,2.5)
Step-by-step explanation:
Answer:
z = 1
Step-by-step explanation:
12/16 = 3z/4
=> 12 x 4/16 = 3z
=> 3z = 12 x 4/16
=> 3z = 12 x 1/4
=> 3z = 3
=> z = 1
Answer:
We accept H₀ . We don´t have enough evidence to express the publisher claim is not true
Step by Step explanation:
We must evaluate if the mean of the price of college textbooks is different from the value claimed by the publisher
n < 30 then we must use t - distrbution
degree of freedom n - 1 df = 22 - 1 df = 21
As the question mentions " different " that means, a two-tail test
At 0,01 significance level α = 0,01 α/2 = 0,005
and t(c) = 2,831
Test Hypothesis
Null Hypothesis H₀ μ = μ₀
Alternative hypothesis Hₐ μ ≠ μ₀
To calculate t(s)
t(s) = ( μ - μ₀ ) /σ/√n
t(s) = ( 433,50 - 385 ) / 86,92 / √22
t(s) = 2,6171
Comparing t(c) and t(s)
t(s) < t(c)
Then t(s) is in the acceptance region we accept H₀. We don´t have enough evidence to claim that mean price differs from publisher claim
Answer:
a) 0.004
b) 0.9609
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 76503
Standard Deviation, σ = 8850
We are given that the distribution of annual salaries is a bell shaped distribution that is a normal distribution.
Formula:
a) P(salary greater than 100,000)
P(x > 100000)
Calculation the value from standard normal z table, we have,
b) P(sample mean annual salary falls between 70,000 and 80,000 dollars)
Sample size, n = 20
Standard error due to sampling =
