Answer:
And we can find this probability with this difference:
And in order to find these probabilities we can use tables for the normal standard distribution, excel or a calculator.
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem'
Let X the random variable that represent the hous spent studying the week before final exams of a population, and for this case we know the distribution for X is given by:
Where
and
We are interested on this probability
And the best way to solve this problem is using the normal standard distribution and the z score given by:
If we apply this formula to our probability we got this:
And we can find this probability with this difference:
And in order to find these probabilities we can use tables for the normal standard distribution, excel or a calculator.
Is there anything else that goes with this question like a picture or something
Answer:
65 i believe
Step-by-step explanation:
first order the data from least to greatest. Then subtract the smallest value from the largest value in the set.
The product of something means multiplying the terms together.
(2x+3) (4x^2-5x+6)
Secondly you need to distribute the terms to each other (Think of problems like FOIL)
2x * 4x^2 + 2x(-5x) + 2x * 6 + 3 * 4x^2 + 3(-5x) + 3 * 6
Then you must take into account that some of the numbers are negative. (minus-plus rules!)
2x * 4x^2 - 2x * 5x + 2x * 6 + 3 * 4x^2 - 3 * 5x + 3 * 6
Now is the tricky part of simplifying everything.
2x * 4x^2 = 8x^3
2x * 5x = 10x^2
2x * 6 = 12x
3 * 4x^2 = 12x^2
3 * 5x = 15x
3 * 6 = 18
8x^3 - 10x^2 + 12x + 12x^2 - 15x + 18
Then you group like terms.
8x^3 - 10x^2 + 12x^2 - 3x + 18
8x^2 + 2x^2 - 3x + 18
The trickiest part of this is distributing all of the terms within the parentheses, once you've done that, it's smooth sailing!
They will see each other every 30 days but won't every 15 days