Answer:
a is the answer, also it's true.
Answer:
5.265
Step-by-step explanation:
<span>Find the wind speed and the plane's airspeed.
:
Let s = speed of the plane in still air
Let w = speed of the wind
then
(s-w) = plane speed against the wind
and
(s+w) = plane speed with the wind
:
Change 3 3/8 hrs to 3.375 hrs
:
The trips there and back are equal distance, (1890 mi) write two distance equations
dist = time * speed
:
3.375(s-w) = 1890
3.0(s + w) = 1890
:
It is convenient that we can simplify both these equations:
divide the 1st by 3.375
divide the 2nd by 3
resulting in two simple equations that can be used for elimination of w
s - w = 560
s + w = 630
----------------adding eliminates w, find s
2s = 1190
s =
s = 595 mph is the plane speed in still air
Find w
595 + w = 630
w = 630 - 595
w = 35 mph is the wind spee</span>
Ln20+ln5=2lnx
ln(20x5)=lnx^2
ln100=1nx^2
100=x^2
square root
x=10
Answer:
Mean SAT score for Stevens High graduates are not the same as the national average.
Step-by-step explanation:
We are given the following information in question:
Population mean, μ = 510
Sample mean, 
= 501
Sample size, n = 50
Alpha, α = 0.10
Sample standard deviation, s = 30
First, we design the null and the alternate hypothesis
We use Two-tailed t test to perform this hypothesis.
Formula:
Putting all the values, we have,
Now,
Since,
We reject the null hypothesis and fail to accept it.
We accept the alternate hypothesis and mean SAT score for Stevens High graduates are not the same as the national average.
