Answer: 1692
Step-by-step explanation:
Formula to find the sample size :

Given : Confidence level : 
⇒ significance level =
z-value for 90% confidence interval (using z-table)=
Prior estimate of the population proportion (p) of customers who keep up with regular vehicle maintenance is unknown.
Let we take p= 0.5
Margin of error : E= 2%=0.02
Now, the required sample size will be :

Simplify , we get

Hence, the required sample size = 1692
Answer:
y = 0.2x + 37
Step-by-step explanation:
A) Find an equation in the form y = mx + b, where x is the number of monthly minutes used and y is the total monthly of the Ringular plan.
(x, y) = (minutes, cost)
(110, 59)
(600, 157)
slope = m = dy/dx
dy/dx = change in y/change in x
m = dy/dx
m = (157 - 59)/(600-110)
m = 98/490
m = 0.2
a) the linear equation:
y - 59 = 0.2(x - 110)
y - 59 = 0.2x - 22
y = 0.2x - 22 + 59
y = 0.2x + 37
Answer:
C. 45 and 141 seconds
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 93 seconds
Standard deviation = 16 seconds
99.7% of running times are approximately between:
By the Empirical rule, within 3 standard deviations of the mean, so between 3 standard deviations below the mean and 3 standard deviations above the mean
3 stnadard deviations below the mean
93 - 3*16 = 45 seconds
3 standard deviations above the mean
93 + 3*16 = 141 seconds
The correct answer is:
C. 45 and 141 seconds
Well if those are the only 3 options of a segment, then there is a 1/3 chance of landing on A, then a 1/3 chance of landing on B, then a 1/3 chance of landing on C. Multiply the fractions together to get 1/27. However that isn't one of your answers. I'm thinking that the spinner has 4 sections, meaning 1/4 chance of A, then 1/4 chance of B, then 1/4 chance of C. Multiply these together to get 1/64, which is one of your answers. That's my input anyway