H = hour
A = 60 + (25h) = ?
B = 120 + (20h) = ?
60 hours because 28 hours for company A x 25 dollars = 700 + starting fee is 60
28 x 25 = 700 + 60 = 760
32 hours for company B x 20 dollars = 640 + starting fee is 120
32 x 20 = 640 + 120 = 760
32 hours + 28 hours = 60 hours all together. It takes 60 hours cost the same
A= 25 x 7 + 60 = 235
25 x 7 = 175 + 60 = 235
B = 20 x 7 + 120 = 260
20 x 7 = 140 + 120 = 260
235 < 260
The cheaper one is A with 235
What does it mean step by step explanation?
Answer:
The smallest sample size n that will guarantee at least a 90% chance of the sample mean income being within $500 of the population mean income is 48.
Step-by-step explanation:
The complete question is:
The mean salary of people living in a certain city is $37,500 with a standard deviation of $2,103. A sample of n people will be selected at random from those living in the city. Find the smallest sample size n that will guarantee at least a 90% chance of the sample mean income being within $500 of the population mean income. Round your answer up to the next largest whole number.
Solution:
The (1 - <em>α</em>)% confidence interval for population mean is:
The margin of error for this interval is:
The critical value of <em>z</em> for 90% confidence level is:
<em>z</em> = 1.645
Compute the required sample size as follows:
Thus, the smallest sample size n that will guarantee at least a 90% chance of the sample mean income being within $500 of the population mean income is 48.
Answer:
Step-by-step explanation:
Thanks!