The confidence interval formula is computed by:
Xbar ± Z s/ sqrt (n)
Where:
Xbar is the mean
Z is the z value
S is the standard deviation
N is the number of samples
So our given are:
90% confidence interval with a z value of 1.645
Sample size 40, 45
Mean 180, 179
Standard deviation 2, 4
So plugging that information in the data will give us a
confidence interval:
For 1:
Xbar ± Z s/ sqrt (n)
= 180 ± 1.645 (2 / sqrt (40))
= 180 ± 1.645 (0.316227766)
= 180 ± 0.520194675
= 179.48, 180.52
For 2:
Xbar ± Z s/ sqrt (n)
= 179 ± 1.645 (4 / sqrt (45))
<span>= 179 ± 1.645 (0.596284794)</span>
therefore, the answer is letter b
Answer:
A. Decreasing linear
Step-by-step explanation:
Answer:
The interest is $1.5 and the amount is $61.5.
Step-by-step explanation:
The total money Dana spent in all is $24.75
<h3>Ratio and proportions</h3>
Ratio are written as fractions of two integers. For instance a/b.
Amount spent for grandmother = $13.75
Amount spent on grand father = 4/5 * 13.75
Amount spent on grand father = $11
Take the sum
Total money spent = $13.75 + $11
Total money spent = $24.75
Hence the total money Dana spent in all is $24.75
Learn more on proportion here: brainly.com/question/19994681
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Hello there!
To find the zeroes or the roots of a function, you just need to set the function equal to 0 then solve for x
f(x) = 2x² - 8x - 10
Set function equal to 0
2x² - 8x - 10 = 0
Now we can factorize the left side
2(x + 1)(x - 5) = 0
Then set factors equal to 0
x + 1 = 0 or x - 5 = 0
x = 0 - 1 or x = 0 + 5
x = -1 or x = 5
Thus,
The roots are -1 and 5
Let me know if you have any questions. As always, it is my pleasure to help students like you~!