Answer:
The value of the test statistic is -2.64.
Step-by-step explanation:
The test statistic is:

In which X is the sample mean,
is the expected(claimed) mean,
is the standard deviation and n is the size of the sample.
An automobile manufacturer claims that its van has a 40.3 miles/gallon (MPG) rating.
This means that 
After testing 250 vans, they found a mean MPG of 39.9. Assume the standard deviation is known to be 2.4.
This means, respectively, that:

So



The value of the test statistic is -2.64.
Answer:
Expression I and IV
Step-by-step explanation:
Expression I simplified :
- 3n + 7 + n + 4n
- 8n + 7
- Expression I = Expression IV
Answer:
sq root of 26
Step-by-step explanation:
One rule of an irrational number is that it cannot be written as an whole fraction, since the other two are fractions, the last must be irrational.
Question 1
The given system of equations is:

Equate the two equations:

Rewrite in standard form:




When we put x=0, in y=3x +6, we get:

One solution is (0,6)
When we put x=-2, into y=3x+6, we get:

Another solution is (-2,0)
The solutions are; (0,6) and (-2,0)
Question 2:
The function is

Let us put x=-x,

This gives:

We can observe that:

This is the property of an even function.
Question 3:
The given function is

The average rate of change of f(x) from x=a to x=b is given as:

This is the slope of the secant line connecting the two points on f(x)
From x=2 to x=6, the average rate of change

The average rate of change is 11
We know that
<span>This problem can be represented through the following equation
</span>
A = A₀(1/2)^t/h
where
A-----------> is the amount of substance left after time t
A₀ ----------> is the original amount---------> 2 g
h-------------> is the half-life-----------> 8 days
for A=0.04 g
t=?
0.04 = 2(1/2)^t/8
0.02 = (1/2)^t/8
Take ln on both sides:
ln(0.02) = ln [(1/2)^t/8]
ln(0.02) = (t/8)(ln 1/2)
t = 8*ln(0.02)/ln(1/2)
t = 45.15 days
the answer is 45.15 days