Answer:
The lower bound of the 80% confidence interval of the average typing speed of a student of this college is of 68.516 words per minute.
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-interval is used to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 20 - 1 = 19
80% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 19 degrees of freedom(y-axis) and a confidence level of . So we have T = 1.328
The margin of error is:
In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 70 - 1.484 = 68.516 wpm.
The lower bound of the 80% confidence interval of the average typing speed of a student of this college is of 68.516 words per minute.
I’m not sure what length your looking for so I found the length in a triangle so the Length AC is the hypotenuse as it is the longest side and is opposite the right angle.
Also I found on for the length of the line segment AC is 12 units long
Answer:
528 cm²
Step-by-step explanation:
First I would calculate the area of the side rectangles:
20 x 9 = 180 cm²
There are two identical rectangles on both sides so i would x2
180 x 2 = 360 cm²
The area of the middle rectangle:
6 x 20 = 120 cm²
The area of the triangles:
Area of a triangle = (Base x Height)/2
8 x 6 = 48
48 ÷ 2 = 24
There are two identical triangles on the bottom and the top so x2
24 x 2 = 48
Now add all the values up:
360 + 120 + 48 = 528 cm²
I hope this helps!
Answer:
28
Step-by-step explanation:
-2+9 (4)=7(4)=28