Answer:
A.
mean = 724.2
Median = 715
Mode = 768
B.
Range = 85
Standard deviation = 29.30
C.
Interval = [665.6, 782.8]
Step-by-step explanation:
Number of samples n = 25
Summation X= 769 + 691 + 699 +730+711+ 765+ 702 718 +719 +712+ 768 +688 +757+695 768 +735 +709 +758 +708+ 693 +736 700+ 687 +772 +715 = 18105
A.
1. Mean = 18105/25
= 724.2
2. Median is the middle value when arranged from the least value to the highest = 715
3. Mode is the number with the highest frequency = 768 (occured two times)
B.
1. Range = highest value - lowest value
Highest value = 772
Lowest value = 687
772-687 = 85
2. Standard deviation = √(X-barX)²/n-1
= √20604/25-1
=√858.5
= 29.30
Please check attachment for the full calculation of the standard deviation
C.
Interval
[Mean - 2(sd), mean + 2(sd)]
= [724.2-2x29.3, 724.2+2x29.3]
=[665.6, 782.8]
Answer:
x = -5/2 y +25/2
Step-by-step explanation:
5y + 2x = 25
Subtract 5y from each side
5y + 2x -5y= -5y+25
2x = -5y +25
Divide by 2
2x/2 = -5y/2 +25/2
x = -5/2 y +25/2
Answer:
14 pounds
Step-by-step explanation:
The given equations can be solved for y by substituting for x. The first equation is convenient for writing x in terms of y.
<h3>Solution</h3>
x = 20 -y . . . . . . . subtract y from the first equation
7(20 -y) +5.5y = 119 . . . . . substitute for x in the second equation
140 -1.5y = 119 . . . . . . . . simplify
21 = 1.5y . . . . . . . . . . . add 1.5y -119 to both sides
14 = y . . . . . . . . . . . .divide by 1.5
14 pounds of soy nuts should be used in the mixture.
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<em>Additional comment</em>
There are many ways to solve a system of two linear equations. The attachments shows a matrix solution using a suitable calculator. It tells us that x=6 and y=14, as we found above.
Answer:
The z-distribution should be used for this problem.
Step-by-step explanation:
The population distribution is assumed to be normal. Which distribution to use?
If we have the standard deviation for the sample, we use the t-distribution.
If we use the standard deviation for the population, we use the z-distribution.
There is a known standard deviation of 2.2 minutes.
This means that 2.2 is the population standard deviation, and thus, the z-distribution should be used for this problem.
Answer:
8 and 8√3
Step-by-step explanation:
Sin90 = b/8
1 x 8 =b
b=8
Tan 30 = 8/a
1/√3 = 8/a
a=8√3