Option D: 21 in is the base length of the triangular base.
Explanation:
Given that a triangular pyramid with a height of 9 inches has a volume of 63 cubic inches.
The height of the triangular base is 6 inches.
We need to determine the base length of the triangular pyramid.
The base length of the triangular pyramid can be determined using the formula,
Substituting 
and 
in the above formula, we get,
Simplifying the terms, we get,
Dividing both sides by 3, we have,
Thus, the base length of the triangular pyramid is 21 in
Hence, Option D is the correct answer.
Answer: 0.375
Step-by-step explanation:
Hey there! If you have any questions feel free to leave them in the comments below.
To find the answer you would divide the numerator by the denominator. 
would be equal to 0.375
~I hope I helped you :)~
Answer:
The critical value that should be used is T = 2.0796.
The 95% confidence interval for the mean repair cost for the dryers is between $91.912 and $105.648.
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-distribution 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 = 22 - 1 = 21
95% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 21 degrees of freedom(y-axis) and a confidence level of 
. So we have T = 2.0796, which is the critical value that should be used.
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 98.78 - 6.868 = $91.912
The upper end of the interval is the sample mean added to M. So it is 98.78 + 6.868 = $105.648
The 95% confidence interval for the mean repair cost for the dryers is between $91.912 and $105.648.
Answer:
79.5 + 5.5x = Y
Step-by-step explanation:
Sumo wrestler gained 5.5 kg per month
After 11 month, he weighed 140 kg.
Let x be his current weight.
Then x + 11(5.5) = 140
x = 140 - 60.5
x = 79.5
If Y is the weight of the wrestler after t months, then the linear equation would be:
79.5 + 5.5t = Y
Answer: One plain roll is 4 dollars and one shiny roll is 6 dollars.
Step-by-step explanation:
lets start by saying
rolls of plain wrapping paper = x
rolls of shiny wrapping paper = y
Kathryn sold 4 plain rolls and 3 shiny rolls for 34 dollars.
4x+3y=34
Eugene sold 4 plain rolls and 2 shiny rolls for 28 dollars
4x+2y=28
Both equations will look like this.
4x+3y=34
-1(4x+2y)=(28)-1
we can multiply the second equation by -1 to get y alone. (doesn't matter which equation). Once you do that, the positive 4x and the negative 4x cancel out, 3y-2y=1y and 34-28=6. you are left with
1y=6 so one shiny roll is 6 dollars.
now use that price to find the cost of the plain roll.
lets use Kathryn's equation
4x + 3(6)=34
4x + 18= 34
-18 -18
4x=16. Divide by 4 to find cost of one plain roll.
16÷4=4. One plain roll costs 4 dollars.
Lets check. Using Kathryn's equation,
4(4) + 3(6)=34
16+18=34
34=34. We are right.
