Answer:
7/12 or in decimal form it is .583
Step-by-step explanation:
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hope this helps!
Answer:
d. t distribution with df = 80
Step-by-step explanation:
Assuming this problem:
Consider independent simple random samples that are taken to test the difference between the means of two populations. The variances of the populations are unknown, but are assumed to be equal. The sample sizes of each population are n1 = 37 and n2 = 45. The appropriate distribution to use is the:
a. t distribution with df = 82.
b. t distribution with df = 81.
c. t distribution with df = 41.
d. t distribution with df = 80
Solution to the problem
When we have two independent samples from two normal distributions with equal variances we are assuming that
And the statistic is given by this formula:
Where t follows a t distribution with
degrees of freedom and the pooled variance
is given by this formula:
This last one is an unbiased estimator of the common variance
So on this case the degrees of freedom are given by:

And the best answer is:
d. t distribution with df = 80
Answer: 2 buses and 4 vans would be needed
Step-by-step explanation:
Let x represent the number of buses that would be needed.
Let y represent the number of vans that would be needed.
There will be six drivers, and two different types of vehicles. This means that
x + y = 6
142 students are going on a field trip. A bus can hold 51 people while a van can hold 10. This means that
51x + 10y = 142 - - - - - - - - - - - 1
Substituting x = 6 - y into equation 1, it becomes
51(6 - y) + 10y = 142
306 - 51y + 10y = 142
- 51y + 10y = 142 - 306
- 41y = - 164
y = - 164/ - 41
y = 4
x = 6 - y = 6 - 4
x = 2
The domain is the input values, which are the x values.
The x values in the given pairs are: 8, 0,4,-3
The domain set is (-3, 0, 4, 8)
Answer:

Step-by-step explanation:
The equation of a circle in standard form is

You are given

In order to put the equation in standard from, we need to complete the square. Since there is no y term, the y part is simply y^2, and there is no need to complete the square for y. For x, we do have an x term, so we must complete the square in x.
Start by grouping the x terms and subtracting 45 from both sides.

Now we need to complete the square for x.

The number that completes the square will go in the blank above, and it will also be added to the right side of the equation.
To find the number you need to add to complete the square, take the coefficient of the x term. It is -18. Divide it by 2. You get -9. Now square -9 to get 81. The number that completes the square in x is 81. Now you add it to both sides of the equation.


Answer: 