Probability At Least One

A website offers a coupon such that each customer has a 17% chance of getting the coupon each day they visit the site. Amira visits the website for 7 consecutive days. What is the probability that at Amira will be offered a coupon on at least one of the days she visits the website?

• .9999

• .2714

• .7286

• .83

When two coins are tossed simultaneously, what are the chances of getting at least one tail?

• 3/4

• 1/5

• 4/5

• 1/4

You work in the quality control department for a cell phone charger company.  There is a 0.005 probability that the charger made is defective.  If you randomly select 250 chargers, what is the probability that at least one charger is defective?

• 0.29

• 0.71

• 0

• 0.995

Determine which of the following distribution is NOT a probability distribution.

• A

• B

• C

• D

Consider the following distribution where X = number of mice caught in an apartment in a night:

Mice | Probability

0 | 0.12

1 | 0.20

2 | 0.31

3 | 0.14

4 | 0.16

5 | 0.07

Which of the following means "trapping at least one mouse?"

• X<1

• X<1

• X>1

• X>1

Is this a probability distribution?

• No, the sum of p(x) does not equal 1.

• Yes, all p(x) are between 0 and 1.

• No, all p(x) are not between 0 and 1.

• Yes, the sum p(x) is 1.

A research team at Cornell University conducted a study showing that approximately 10% of all businessmen who wear ties wear them so tightly that they actually reduce blood flow to brain, diminishing cerebral functions. At a board meeting of 20 businessmen, all of whom wear ties, what is the probability that at least one tie is too tight?

• 27.0%

• 12.2%

• 73.0%

• 87.8%

The student who makes the morning announcements has the bad habit of saying “like” all the time. The chance that they say “like” in a sentence is 60%. You decide to keep a tally of how many times they say like. If they say 350 sentences this week, what is the probability that they will say “like” at least 200 times?

• 0.87

• 0.13

• 0.85

• 0.15

Which formula would you use in the following case? A research team at Cornell University conducted a study showing that approximately 10% of all businessmen who wear ties wear them so tightly that they actually reduce blood flow to brain, diminishing cerebral functions. At a board meeting of 20 businessmen, all of whom wear ties, what is the probability that at least one tie is too tight?

• (a)

• (b)

What is "q" in the following scenario?

A research team at Cornell University conducted a study showing that approximately 10% of all businessmen who wear ties wear them so tightly that they actually reduce blood flow to brain, diminishing cerebral functions. At a board meeting of 20 businessmen, all of whom wear ties, what is the probability that at least one tie is too tight?

• 1/20

• 0.1

• 0.9