Answer:
C. If I lower my grades then I work alone
Step-by-step explanation:
In logic, the contrapositive of a conditional statement, is .
In other words, the contrapositive of "If P then Q" is "If not Q, then not P".
The given conditional statement is:
"If I form a study group then I raise my grades."
We can break this conditional statement into the following propositional statements:
P : I form a study group
¬P : I work alone
Q : I raise my grades
¬Q : I lower my grades
The contrapositive of "If I form a study group then I raise my grades." becomes:
" If I lower my grades then I work alone"
The correct choice is C
Answer:
15. A
16. B
17. B
18. C
Step-by-step explanation:
Answer: C.
Step-by-step explanation:
10 + (-5) = 10 - 5 = 5
-11 + 20 = 20 + (-11) = 20 - 11 = 9
102 + (-1) = 102 - 1 = 101
<span>-20 + 60 = 60 + (-20) = 60 - 20 = 40</span>
Answer:
And we can find this probability using excel or the normal standard tabe and we got:
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 temperatures 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 excel or the normal standard tabe and we got: