Question 1

With a mean of 95 and an SD of 12, what is the probability of selecting at random a score of between 89 and 101?

Accepted Answer

The answer of With a mean of 95 and an...

Question 2

A certain air-force missile has an average range of 1500 miles with a standard deviation of 62 miles. What is the probability that any single shot will travel 1400 miles or less?

Accepted Answer

The answer of A certain air-force missile has an average...

Question 3

Using data from the previous problem, what is the probability of selecting an inmate who had NOT recidivated?
A) .36
B) .64
C) .50
D) .46.

Accepted Answer

The answer of Using data from the previous problem, what...

Question 4

With a mean of 60 and an SD of 4, what is the probability of selecting at random a score between 56 and 58?

Accepted Answer

The answer of With a mean of 60 and an...

Question 5

With a mean of 55 and an SD of 6, what is the probability of selecting at random someone scoring between 48 and 50?

Accepted Answer

The answer of With a mean of 55 and an...

Question 6

At a certain race track, the horses run the mile in an average time of 135 seconds, with an SD of 13 seconds. What is the probability of selecting at random a horse that could run the mile in 130 seconds or less?

Accepted Answer

The answer of At a certain race track, the horses...

Question 7

In a certain house of correction, 64% percent of the current population of inmates had recidivated. What is the probability of selecting an inmate at random who had recidivated?
A) .36
B) .64
C) .50
D) .46

Accepted Answer

The question is asking for the probability of selecting an inmate at random who had recidivated. We are given that 64% of the current population has recidivated, so the answer is simply .64 or 64%. Therefore, choice B is the correct answer.

Question 8

At a certain prison it was found that 71% of the inmates had had a first arrest at the age of 15 or younger. It was also found that 70% of the population were identified as having had a drug problem. What is the probability of selecting at random an inmate who had been arrested at 15 or younger and had also been identified as having a drug problem?
A) .14
B) .50 
C).95
D) .46

Accepted Answer

The answer of At a certain prison it was found...

Question 9

With a mean of 70 and an SD of 10, what is the probability of selecting a score of between 75 and 90?

Accepted Answer

The answer of With a mean of 70 and an...

Question 10

The mean IQ in a certain sorority is 120 with an SD of 5. What is the probability of selecting at random a student whose IQ is between 130 and 135?

Accepted Answer

The answer of The mean IQ in a certain sorority...

Question 11

Using data from the previous problem, what is the probability of selecting at random a participant who had had a losing evening?
A) .12
B) .24
C) .48
D) .88

Accepted Answer

The answer of Using data from the previous problem, what...

Question 12

At a certain college, the mean college-board score in math is 400 with an SD of 97. What is the probability of selecting at random a student who scored between 370 and 450?

Accepted Answer

The answer of At a certain college, the mean college-board...

Question 13

If the probability of a certain event is .50 and the probability of a second event is .50, what is the probability of having the first event occur OR the second event occur?
A) .25
B) .50
C) .75
D) 1.00

Accepted Answer

The probability of having the first event occur OR the second event occur is the sum of the probabilities of each event occurring, minus the probability of both events occurring. In this case, the probability of both events occurring is 0, so the probability of having the first event occur OR the second event occur is .50 + .50 = 1.00.

Question 14

The average life of a certain light bulb is 200 hours with an SD of 27 hours. What is the probability of selecting at random a bulb lasting 150 hours or less?

Accepted Answer

The answer of The average life of a certain light...

Question 15

At a certain casino on a certain day, 12% of the participants left at the end of the evening as winners (had more money than when they entered). What is the probability of selecting at random a participant who had had a winning evening? 
A).12
B) .24
C) .48
D) .88

Accepted Answer

The probability of selecting a participant who had a winning evening is directly given as 12%, which translates to 0.12 in decimal form, matching choice A.

Question 16

With a mean of 40 and an SD of 20.45, what is the probability of selecting at random a score of 45 or higher?

Accepted Answer

The answer of With a mean of 40 and an...

Quiz 6: Probability

With a mean of 95 and an SD of 12, what is the probability of selecting at random a score of between 89 and 101?

A certain air-force missile has an average range of 1500 miles with a standard deviation of 62 miles. What is the probability that any single shot will travel 1400 miles or less?

Using data from the previous problem, what is the probability of selecting an inmate who had NOT recidivated?

With a mean of 60 and an SD of 4, what is the probability of selecting at random a score between 56 and 58?

With a mean of 55 and an SD of 6, what is the probability of selecting at random someone scoring between 48 and 50?

At a certain race track, the horses run the mile in an average time of 135 seconds, with an SD of 13 seconds. What is the probability of selecting at random a horse that could run the mile in 130 seconds or less?

In a certain house of correction, 64% percent of the current population of inmates had recidivated. What is the probability of selecting an inmate at random who had recidivated?

With a mean of 70 and an SD of 10, what is the probability of selecting a score of between 75 and 90?

The mean IQ in a certain sorority is 120 with an SD of 5. What is the probability of selecting at random a student whose IQ is between 130 and 135?

Using data from the previous problem, what is the probability of selecting at random a participant who had had a losing evening?

At a certain college, the mean college-board score in math is 400 with an SD of 97. What is the probability of selecting at random a student who scored between 370 and 450?

If the probability of a certain event is .50 and the probability of a second event is .50, what is the probability of having the first event occur OR the second event occur?

The average life of a certain light bulb is 200 hours with an SD of 27 hours. What is the probability of selecting at random a bulb lasting 150 hours or less?

At a certain casino on a certain day, 12% of the participants left at the end of the evening as winners (had more money than when they entered) . What is the probability of selecting at random a participant who had had a winning evening?

With a mean of 40 and an SD of 20.45, what is the probability of selecting at random a score of 45 or higher?