Answer:
0.0323 = 3.23%. Is unusual
Step-by-step explanation:
Using the normal distribution we can find z value with the mean and standard deviation as follows. x is the value we want to know its probability
z = (x - mean)/standard deviation
z = (5-8.54)/1.91
z = -1.85
Using z tables for normal distribution, for z = 1.85, we have an area under the curve of 0.9677. Since we want to know the probability for 5 minutes or less, we have to substract from
p = 1- 0.9677
p = 0.0323
An event with a probability less than 5% is considered unusual.
Answer:
D
Step-by-step explanation:
Area of H = 25pi
Area of J = 225pi
225pi/25pi = 9
There exists a similar question that would lead to the relationship of the given circumference to the unknown value. The radius of the larger circle is 12 cm. The formula for determining the circumference is,
C = 2πr
Substituting the known value,
C = 2π x 12 cm = 24π cm
Thus, the answer is letter B.
Answer: a) 683 b) 1067
Step-by-step explanation:
The confidence interval for population proportion is given by :-
a) Given : Significance level :
Critical value : 
Margin of error : 
Formula to calculate the sample size needed for interval estimate of population proportion :-
Hence, the required sample size would be 683 .
b) If no estimate of the sample proportion is available then the formula to calculate sample size will be :-
Hence, the required sample size would be 1067 .
