9 - c = -13
-c = -13 - 9
-c = - 22
c = 22 <===
Total voters=v=80
total no. of democrats=d=65
total no. of republicans=r=15
probability of democrats=p1=65/80=0.8125
probability of republicans=p2=15/80=0.1875
probability of a democrat or a republican=p1+p2=0.8125+0.1875=1 <span />
Answer:
The answer is A.) R
R is in the correct correspondence with B.
Answer:
And we can find this probability using the complement rule and with the normal standard table or excel:
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 average household spent 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 using the complement rule and with the normal standard table or excel: