Answer:
Lewis's friend walked with him 9/25 miles
Step-by-step explanation:
Given that
Lewis walked 9/10 of a mile
And His friend accompanied him on 2/5 of the way.
This is a simple question of fraction multiplication
The fraction 2/5 has to multiplied with the miles walked by lewis
So
Hence,
Lewis's friend walked with him 9/25 miles
The 95% confidence interval of the population mean, in years, is (4.3, 5.3). 4 years is not part of the confidence interval, which means that it contradicts the fact that 39% of students get their college degree in four years.
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To solve this question, we need to find the confidence interval for the amount of time it takes the students to get the degree.
We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.
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The first step to solve this problem is finding how many degrees of freedom,which is the sample size subtracted by 1. So
df = 80 - 1 = 79
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95% confidence interval
Standard level of confidence, we have to find a value of T, which is found looking at the t table, with 79 degrees of freedom(y-axis) and a confidence level of . So we have T = 1.9905.
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The margin of error is:
In which s is the standard deviation of the sample and n is the size of the sample.
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The lower end of the interval is the sample mean subtracted by M. So it is 4.8 - 0.3 = 4.3 years.
The upper end of the interval is the sample mean added to M. So it is 4.8 + 0.3 = 5.3 years.
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The 95% confidence interval of the population mean, in years, is (4.3, 5.3). 4 years is not part of the confidence interval, which means that it contradicts the fact that 39% of students get their college degree in four years.
A similar question is given at brainly.com/question/24278748
Answer:
115.48
Step-by-step explanation:
This shape can be split into two distinct shapes
Two halves of a semi circle, and a rectangle in between
Circle:
Putting both halves of the semi circle together will give you a full circle. The diameter of the circle is given (7m).
The area of a circle is A = π
The radius, r, is half of the diameter, so 7 / 2 = 3.5m
A = π
A = π *
A = 38.38
Rectangle:
The area of a rectangle is A = h b
The height, h, is known at 7m
The base, b, can be found by removing the length from the dot to the end of the semi circles. This length is the radius of the semi circles, 3.5m
Removing the radius from the total length given
18 - 3.5 - 3.5 = 11m
The base is 11m
A = h b
A = 7 * 11 = 77
Total Area = Circle area + Rectangle area
Total Area = 38.38 + 77 = 115.48