Answer: $10
Step-by-step explanation:
Let's analize the information given: We know that she had $94 to spend on 8 books and after buying these books she had $14. So, we need to calculate the amount of money she spent. Subtract $94 and $14:
Then, to calculate the cost of each book, we need to divide the "Total spent" by 8:
Answer:
In order to find the variance we need to find first the second moment given by:
And replacing we got:
The variance is calculated with this formula:
And the standard deviation is just the square root of the variance and we got:
Step-by-step explanation:
Previous concepts
The expected value of a random variable X is the n-th moment about zero of a probability density function f(x) if X is continuous, or the weighted average for a discrete probability distribution, if X is discrete.
The variance of a random variable X represent the spread of the possible values of the variable. The variance of X is written as Var(X).
Solution to the problem
LEt X the random variable who represent the number of defective transistors. For this case we have the following probability distribution for X
X 0 1 2 3
P(X) 0.92 0.03 0.03 0.02
We can calculate the expected value with the following formula:
And replacing we got:
In order to find the variance we need to find first the second moment given by:
And replacing we got:
The variance is calculated with this formula:
And the standard deviation is just the square root of the variance and we got:
It sounds like everything is being described in reference to angle A, so a good starting point is to pick a variable to represent the measure of angle A. I'm going to use "a" for that.
Next, I'm going to take the verbal descriptions in the problem and "translate" them into "math language". They say angle B is 5 times angle A, so that means the measure of angle B is actually 5a. The size of angle C is 5 degrees less than 4 times the size of A, so that translates to 4a-5.
We now know the following:
Angle A: a
Angle B: 5a
Angle C: 4a-5
Now, to find the value of a, we need to remember that all the angles in a triangle add up to 180 degrees.
So we have: a+5a+4a-5 = 180
We can solve that equation by combining like terms to get: 10a-5=180
We can add 5 to both sides: 10a =185
And divide by 10: a = 18.5
That tells us the measure of angle A! (It's 18.5 degrees). Now we can go back and find B by multiplying A by 5. We get 92.5 degrees for that.
Finally, we can find C by taking 4*18.5-5. We get 69 degrees for that.
One last thing-- let's check that they really do add up to 180! 69+92.5+18.5 = 180. Yep!
Hope that helps you!!
Answer:
addition
Step-by-step explanation:
18 ( <u>d</u> - 9 ) = 198
3
divide both side by 18
<u> d </u>- 9 = <u>198
</u>
3 18
<u>d</u> - 9 = 11
3
multiply both sides by 3
d - 27 = 33
add 27 to both sides
d = 33 + 27
lastly, add them together
d = 60
therefore, the last step is addition
Answer:
x =
Step-by-step explanation:
2x – 4 – (x + 2) = 6x is the given equation
Now simplifying both sides, we get
2x - 4 - x - 2 = 6x
taking like terms on each side of the equality, we get
2x - x - 6x = 4 + 2
or, -5x = 6
or x =
hence, the value of x =