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:
D. 1662 cm
Step-by-step explanation:
A=πr2=π•23≈1661.90251cm²
which is 1661.9
but of course you have to round up for 1662 cm :)
Answer:
Step-by-step explanation:
Your right I think it's c
Answer:
6x+3
Step-by-step explanation:
You first must distribute the negative sign to 3x+7, giving you -3x+7. Then you combine like terms (the 9x+(-3x) and 10+(-7)). This would give you 6x+3
Plot a point at the y-intercept of -2 or y = -2
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From there make a straight horizontal line
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Then Shade the upper-half of that line one color This shaded part stands for
Y > -2
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Shade the lower half a different color, this stands for y ≤ 6
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That should be it!
