Answer:
190
Step-by-step explanation:
Data provided in the question:
Confidence level = 99%
Therefore,
α = 1% = 0.01
[ from standard normal table ]
z-value for
= 2.58
Margin of error, E = $0.06
Standard deviation, σ = $0.32
Now,
n = 
Here,
n is the sample size (or the minimum number of gas stations )
on substituting the respective values, we get
=
=
= 13.76²
= 189.3376 ≈ 190
Hence,
minimum number of gas stations that she should include in her sample is 190
Answer:
B
Step-by-step explanation:
P(AUB)=P(A)+P(B)-P(A∩B)
191/400=7/20+P(B)-49/400
P(B)=191/400+49/400-7/20=240/400-7/20=12/20-7/20=5/20=1/4

Sounds like that to me but that is symbolically showing of that's what your teacher means as mathematical sentence
8m^2+18m+9=0
Multiply 2m by 4m to get 8m^2. Multiply 2m by 3 to get 6m. Multiply 3 by 4m to get 12m. Add the 6m and 12m to make 18m. Multiply 3 by 3 to get the integer 9. Set it all equal to 0.
The p-value of the test is the calculated probability. Hence, the probability must be 18/380. In simplified terms, this is equal to 0.0474 or 4.74%. This is the p-value of the test. The null hypothesis is p < 6%. According to the test, the p-value is 4.74%. Therefore, the null hypothesis is accepted.
The answer is not among the choices. The answer must be 0.0474 or 4.74%.