Answer:
189 components must be sampled.
Step-by-step explanation:
We have that to find our 
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of 
.
That is z with a pvalue of 
, so Z = 2.575.
Now, find the margin of error M as such
Assume that component lifetimes are normally distributed with population standard deviation of 16 hours.
This means that 
How many components must be sampled so that a 99% confidence interval will have margin of error of 3 hours?
n components must be sampled.
n is found when M = 3. So
Rounding up:
189 components must be sampled.
Answer:
{x | x<3 or x>1}
Step-by-step explanation:
x+2<5
x<5-2
x< 3
x-7> -6
x> -6+7
x>1
symbol U means union
Answer:
area of composite shapes is area of rectangle plus area of square what do I know I'm just in 8th grad
Answer:
Step-by-step explanation:
(7/12) of 840 attended the concert:
(7/12)*(840) = 490 students attended the Spring Concert.
(840 - 490) = 350 did not attend
(350/840) is the fraction of students who did not attend. This can be reduced to (35/84)
(350/840) = 0.4167 or 41.67% did not attend.
I think A which is 4in but not sure
