Answer:
c.145.3 to 154.7.
Step-by-step explanation:
We have 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 Z-table as such z has a p-value of .
That is z with a p-value of , so Z = 1.645.
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.
The lower end of the interval is the sample mean subtracted by M. So it is 150 - 4.7 = 145.3.
The upper end of the interval is the sample mean added to M. So it is 150 + 4.7 = 154.7.
Thus the correct answer is given by option c.
Answer:
3m I believe I'm not fully sure
Ok so
we don't know the sign so it could be
4x^2-8x+60 or
4x^2-8x-60
( if it is the first one, go to AAAAAAA
if it is second one go to BBBBBBBBBBB)
to find the zero fo the function, set the fnction to zero
then factor since if you had xy=0, then assume that x and y=0
AAAAAAAAAA
4x^2-8x+60=0
4(x^2-2x+15)=0
4 you get a nonreal root so the missing sign is probably a negative sign
if you were to graph this one, there is no x intercept
BBBBBBBBB
4x^2-8x-60=0
4(x^2-2x-15)=0
4(x-5)(x-3)=0
x-5=0
x=5
x-3=0
x=3
3<5
smallest zero is 3
I would say the smallest zero is 3
Answer:
It takes them approximately 27 minutes to mow the lawn if they are working together.
Step-by-step explanation:
Wilma can mow a lawn in 80 minutes. This means she can mow at the rate of 1 lawn in 80 minutes. We can write this rate as R = 1/80
Melissa can mow the same lawn in 40 minutes. This means she can mow at the rate of 1 lawn in 40 minutes. We write the rate as R = 1/40.
Now, if the are working together, we need to determine how long it would take for them to mow a lawn. Let this rate be 1/x.
What we want to find is
1/80 + 1/40 = 1/x
Multiply through by 80, we have
1 + 2 = 80/x
3 = 80/x
Take reciprocals of both sides
x/80 = 1/3
x = 80/3
= 1600 seconds
Approximately 27 minutes
Answer:
Alternate interior