Answer:
95% confidence interval for the mean number of months is between a lower limit of 6.67 months and an upper limit of 25.73 months.
Step-by-step explanation:
Confidence interval is given as mean +/- margin of error (E)
Data: 5, 15, 12, 22, 27
mean = (5+15+12+22+27)/5 = 81/5 = 16.2 months
sd = sqrt[((5-16.2)^2 + (15-16.2)^2 + (12-16.2)^2 + (22-16.2)^2 + (27-16.2)^2) ÷ 5] = sqrt(58.96) = 7.68 months
n = 5
degree of freedom = n-1 = 5-1 = 4
confidence level (C) = 95% = 0.95
significance level = 1 - C = 1 - 0.95 = 0.05 = 5%
critical value (t) corresponding to 4 degrees of freedom and 5% significance level is 2.776
E = t×sd/√n = 2.776×7.68/√5 = 9.53 months
Lower limit of mean = mean - E = 16.2 - 9.53 = 6.67 months
Upper limit of mean = mean + E = 16.2 + 9.53 = 25.73 months
95% confidence interval is (6.67, 25.73)
1 to 45 is 45
90 divided by 2 is 45
135 divided by 4 is 45
180 divided by 4 is 45
all of them have the same relationship and a proportional to each other
Answer:
A
Step-by-step explanation:
Taking the square root of both sides.
<span>MP3 player is $60
</span><span>The selling price is $105
</span><span>A classmate says that the markup is 175% because $105/$60=1.75 . Is your classmate correct?
No. IT's not correct
Original price $60
Selling price $105
$105 - $60 = $45
So
45/60 x 100 = 75%
Price is markup 75% from $60 to $105</span>
