Answer:
For this case the 95% confidence interval is given (63.5 , 74.4) and we want to conclude about the result. For this case we can say that the true mean of heights for male students would be between 63.5 and 74.4. And the best answer would be:
b. The doctor can be 95% confident that the mean height of male students at the college is between 63.5 inches and 74.4 inches.
Step-by-step explanation:
Notation
represent the sample mean for the sample
population mean (variable of interest)
s represent the sample standard deviation
n represent the sample size
Solution to the problem
The confidence interval for the mean is given by the following formula:
(1)
In order to calculate the mean and the sample deviation we can use the following formulas:
(2)
(3)
In order to calculate the critical value 
we need to find first the degrees of freedom, given by:
For this case the 95% confidence interval is given (63.5 , 74.4) and we want to conclude about the result. For this case we can say that the true mean of heights for male students would be between 63.5 and 74.4. And the best answer would be:
b. The doctor can be 95% confident that the mean height of male students at the college is between 63.5 inches and 74.4 inches.
Solution: We are given:
Predicted Sales by Sameera 
Actual Sales by Sameera 
Now to find the Percent error, we have to use the below formula:
Therefore, the percent error is 
Answer:
Mrs. Wright's paycheck is $630
Step-by-step explanation:
Let x = Mrs. Wright's paycheck.
Mrs. Wright spent 2/9 of her paycheck on food. This means that the amount of money spent on food is 2/9 × x = 2x/9
She spent 1/3 on rent. This means that the amount spent on rent is
1/3 ×x x = x/3
Amount she spent on food and rent is x/3 + 2x/9 =3x + 2x /9
= 5x/9
The remainder is her pay check - the amount that she spent on food and rent. It becomes
x - 5x/9 = (9x- 5x)/9 = 4x/9
She spent 1/4 of the remainder on transportation. It means that she spent 1/4 × 4x/9 = x /9 on transportation.
Amount left = 4x /9 - x/9= 3x/9
She had $210 left. Therefore,
210 = 3x/9
3x = 9×210 = 1890
x = 1890/3
x = $630
Answer:
£495 million
Step-by-step explanation:
To find out the total cost of the land, we need to first calculate the area of the land.
Step 1: Find area of right angled triangle ADC
AD = 5 km,
DC = 12 km
Area of the right triangle = ½*a*b
a = 5km
b = 12km
Area = ½*5*12
= 5*6
Area of ADC = 30 km²
Step 2: Find the area of triangle ABC
First, let's find the length of AC using Pythagorean theorem
AC² = AD² + DC²
AC² = 5² + 12² = 25 + 144
AC = √169
AC = 13km
Area of ∆ABC = ½*AB*AC*sin(30°)
= ½*6*13*0.5
= 3*13*0.5
Area of ∆ABC = 19.5 km²
Total area of the land = area of ∆ADC + ∆ABC = 30 + 19.5 = 49.5 km²
Step 3: calculate how much the land costs
If the land costs £10 million per km²,
Cost of 49.5 km² = 49.5 × 10 = £495 million
