A group of friends wants to go to the amusement park. They have no more
1 answer:
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ANSWER
The other zero is
EXPLANATION
The axis of symmetry serves as the midpoint of the two zeroes.
We were given that the axis of symmetry of the quadratic equation is
We were also given that, one of the zeroes of the quadratic equation is
Let the other zero of the quadratic equation be
,then, we apply the midpoint formula to find the value of
Since it is the x-values of the intercepts that gives the solution, we use only the x-value part of the midpoint formula which is given by,
We substitute to obtain,
We multiply through by 2 to get,
This implies that,
The other zero is
EXPLANATION
The axis of symmetry serves as the midpoint of the two zeroes.
We were given that the axis of symmetry of the quadratic equation is
We were also given that, one of the zeroes of the quadratic equation is
Let the other zero of the quadratic equation be
,then, we apply the midpoint formula to find the value of
Since it is the x-values of the intercepts that gives the solution, we use only the x-value part of the midpoint formula which is given by,
We substitute to obtain,
We multiply through by 2 to get,
This implies that,
Answer:
A sample size of 385 is needed.
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 = 1.96.
Now, find the margin of error M as such
In which is the standard deviation of the population and n is the size of the sample.
You feel that a reasonable estimate of the standard deviation is 10.0 hours.
This means that
What sample size is needed so that the expected margin of error of your estimate is not larger than one hour for 95% confidence?
A sample size of n is needed. n is found when M = 1. So
Rounding up:
A sample size of 385 is needed.