Normal distribution Examples
1) A physical fitness association is including the mile run in its secondaryschool fitness test. The
time for this event for boys in secondary school is known to possess a normal distribution with a
mean of 450 seconds and a standard deviation of 60 seconds. Find the probability that a randomly
selected boy in secondary school can run the mile in less than 312 seconds.
A) .5107 B) .0107 C) .4893 D) .9893
2) The amount of corn chips dispensed into a 20ounce bag by the dispensing machine has been
identified as possessing a normal distribution with a mean of 20.5 ounces and a standard deviation
of 0.2 ounce. What proportion of the 20 ounce bags contain more than the advertised 20 ounces of
chips?
A) 0.5062 B) 0.9938 C) 0.4938 D) 0.0062
3) 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 3.5 minutes and a standard deviation of 1 minute. Find the
probability that a randomly selected college student will take between 2.0 and 4.5 minutes to find a
parking spot in the library lot.
A) .2255 B) .7745 C) .0919 D) .4938
4) The amount of soda a dispensing machine pours into a 12 ounce can of soda follows a normal
distribution with a mean of 12.54 ounces and a standard deviation of 0.36 ounce. The company
receives complaints from consumers who actually measure the amount of soda in the bottles and
claim that there was less than the advertised 12 ounces of soda. What proportion of the soda cans
contain less than the advertised 12 ounces of soda?
A) .4332 B) .5668 C) .9332 D) .0668
5) The amount of soda a dispensing machine pours into a 12 ounce can of soda follows a normal
distribution with a mean of 12.36 ounces and a standard deviation of 0.24 ounce. The cans only
hold 12.60 ounces of soda. Every can that has more than 12.60 ounces of soda poured into it causes
a spill and the can needs to go through a special cleaning process before it can be sold. What is the
probability a randomly selected can will need to go through this process?
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
This is the end of the preview.
Sign up
to
access the rest of the document.
 Fall '08
 STAFF
 Normal Distribution, Standard Deviation, Sarah

Click to edit the document details