Answer:
Simple random sampling survey method
Step-by-step explanation:
A simple random sampling is an unbiased survey technique Hence it will represent all the parts of the city's population.
In statistics, a simple random sample is a subset of individuals (a sample) chosen from a larger set (a population). Each individual is chosen randomly and entirely by chance, such that each individual has the same probability of being chosen at any stage during the sampling process
A. The point estimate of μ1 − μ2 is calculated using the value of x1 - x2, therefore:
μ1 − μ2 = x1 – x2 =
7.82 – 5.99
μ1 − μ2 = 1.83
B. The formula for
confidence interval is given as:
Confidence interval
= (x1 –x2) ± z σ
where z is a value
taken from the standard distribution tables at 99% confidence interval, z =
2.58
and σ is calculated
using the formula:
σ = sqrt [(σ1^2 /
n1) + (σ2^2 / n2)]
σ = sqrt [(2.35^2 /
18) + (3.17^2 / 15)]
σ = 0.988297
Going back to the
confidence interval:
Confidence interval
= 1.83 ± (2.58) (0.988297)
Confidence interval
= 1.83 ± 2.55
Confidence interval
= -0.72, 4.38
I believe the answer is “A”
C. For each hour he works, his earnings go up by $8.
Answer:
x+10 x ≠ 60
Step-by-step explanation:
(x^2−50x−600)
----------------------
(x−60)
Factor the numerator
(x-60)(x+10)
-------------------
(x-60)
Cancel the like terms
x+10