Answer:
1.282, -0.5244,...
Step-by-step explanation:
We know that Z is a standard normal variate with mean =0, and std dev =1
a) z-score separates the highest 10% from the rest of the scores
= 90th percentile = 1.282
b) z-score separates the lowest 30% from the rest of the scores
= 30th percentile = -0.5244
c) z-score separates the lowest 40% from the rest of the scores
= 40th percentile = -0.2533
d) z-score separates the lowest 20% from the rest of the score
=20th percentile = -0.8416
Answer:
2 Paul's Survey sample only included tenth graders
Step-by-step explanation:
The reson why this is your answer is simple
Because this is true, he ONLY surveyed tenth-graders. He should have found for all of the students, including the other 1,100 students that didn't get surveyed.
Thanks!
Answer:
Option B is right
Step-by-step explanation:
P(A or B)
In set theory if A and B are two sets we have either A occurs or B occurs or both as
P(A or B) = P(AUB)
This implies that A occurs or B occurs
Probability is calculated as P(A)+P(B)-P(AB)
P(AB) here represents both occurring and this is subtracted as this was added two times
Option A is wrong because this is AB
Option C is wrong because it is not necessary A occurs first
D is wrong because this is A'UB' where A' represents the complement of A
So correct answer out of four options is
B. the probability that in a single trial, event A occurs, event B occurs, or they both occur.