The tread life of a particular brand of tire is a random variable best described by a normal distribution with a mean of 60,000 miles and a standard deviation of 2800 miles. What is the probability a particular tire of this brand will last longer than 57,200 miles?

0.1587

0.8413

0.7266

0.2266

Furnace repair bills are normally distributed with a mean of 273 dollars and a standard deviation of 25 dollars. If 100 of these repair bills are randomly selected, find the probability that they have a mean cost between 273 dollars and 275 dollars.

0.2881

0.2119

0.5517

0.7881

A quiz consists of 10 multiple choice questions, each with five possible answers, one of which is correct. To pass the quiz a student must get 60% or better on the quiz. If a student randomly guesses, what is the probability that the student will pass the quiz?

0.060

0.377

0.205

0.006

In a recent survey, 60% of the community favored building a health center in their neighborhood. If 14 citizens are chosen, find the probability that exactly 5 of them favor the building of the health center.

0.041

0.207

0.357

0.600

Suppose a brewery has a filling machine that fills 12 ounce bottles of beer. It is known that the amount of beer poured by this filling machine follows a normal distribution with a mean of 12.18and a standard deviation of 0.04 ounce. Find the probability that the bottle contains fewer thanof beer.

0.4938

0.5062

0.0062

0.9938

A committee consisting of 6 people is to be selected from eight parents and four teachers. Find the probability of selecting three parents and three teachers.

2/33

8/33

10/11

100/231

A farmer was interested in determining how many grasshoppers were in his field. He knows that the distribution of grasshoppers may not be normally distributed in his field due to growing conditions. As he drives his tractor down each row he counts how many grasshoppers he sees flying away. After several rows he figures the mean number of flights to be 57 with a standard deviation of 12. What is the probability of the farmer will count 60 or more flights on average in the next 40 rows down which he drives his tractor?

0.4429

0.0571

0.5710

0.9429

The owner of a computer repair shop has determined that their daily revenue has mean $7200 and standard deviation $1200. The daily revenue totals for the next 30 days will be monitored. What is the probability that the mean daily revenue for the next 30 days will be less than $7000?

0.4325

0.1814

0.5675

0.8186

There are 26 chocolates in a box, all identically shaped. There 5 are filled with nuts, 8 with caramel, and 13 are solid chocolate. You randomly select one piece, eat it, and then select a second piece. Find the probability of selecting 2 nut candies.

25/676

1/50

5/169

2/65

The length of time it takes college students to find a parking spot in the library parking lot follows a normal distribution with a mean of 3.0 minutes and a standard deviation of 1 minute. Find the probability that a randomly selected college student will take between 1.5 and 4.0 minutes to find a parking spot in the library lot.

0.4938

0.7745

0.2255

0.0919

11.A box contains 23 widgets, 4 of which are defective. If 4 are sold at random, find the probability that (a) all are defective (b) none are defective.

4/23;19/23

1/23;4/23

1/8855; 3876/8855

1/212,520; 1/53,130

According to the Federal Communications Commission, 70% of all U.S. households have vcrs. In a random sample of 15 households, what is the probability that the number of households with vcrs is between 10 and 12, inclusive?

0.4053

0.2061

0.7

0.5947

A physical fitness association is including the mile run in its secondary-school fitness test. The time for this event for boys in secondary school is known to possess a normal distribution with a mean of 440 seconds and a standard deviation of 40 seconds. Find the probability that a randomly selected boy in secondary school can run the mile in less than 348 seconds.

0.4893

0.5107

0.0107

0.9893