Answer:
7,859.92
Step-by-step explanation:
Add up the additions starting with what she started off with in the bank and subtract 4,200.00
Answer: 24.67 ≤ μ ≤ 27.33
Step-by-step explanation:
From the information given: n = 81 students, Sample mean (x bar) = 26 and sample standard deviation (s) = 6.
Since the population standard deviation in unknown we use the student t distribution to estimate the mean. The mean is estimated as follows:
X bar - t (∝/2, n-1) x s/sqrt n ≤ μ ≤ X bar + t (∝/2, n-1) x s/sqrt n
Degrees of freedom, df = n - 1 = 81 - 1 = 80
∝ = 100 - 95 = 5% = 0.05 thus ∝/2 = 0.025
From the t distribution t (0.025,80) = 1.990
Substituting into the formula:
26 - 1.990 x 6/sqrt 81 ≤ μ ≤ 26 + 1.990 x 6/sqrt 81
24.67 ≤ μ ≤ 27.33
Answer:
Step-by-step explanation:
So, we have to divide the total amount of the profit they made by the cost per car wash. This is because we have to find the unit rate. So, the problem would be $853 divided by $5. Now the answer would be 170.6, but if you round the answer, it would be approximately 170 cars. We have to round, because 0.6 is NOT a full car, and we need to know how MANY CARS were washed. We wouldn't do anything with the $12 they spent, because the problem does NOT state anything about the amount of cash they have AFTER the supplies were bought.