WorksheetsProbabilities of At-Least
Total questions: 13
Worksheet time: 1hrs 1mins
Name
Class
Date
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?
a)
27.0%
b)
12.2%
c)
73.0%
d)
87.8%
2.
You are playing against Miss Soldan in a student/faculty basketball game. You know she is terrible at free throws (she has an 8% accuracy rate), so you keep fouling her. If she attempts 18 free throws, what is the probability that she makes more than 3 of them?
a)
0.05
b)
0.95
c)
0.17
d)
0.83
3.
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?
a)
0.87
b)
0.13
c)
0.85
d)
0.15
4.
According to a recent survey, 15% of houses in America are haunted by a ghost. If your neighborhood has 40 houses, what is the probability that 5 or more of them are haunted?
a)
0.74
b)
0.26
c)
0.57
d)
0.43
5.
You have decided to drop out of school and move to Vegas, where you will learn to count cards and get rich. If you draw 12 cards out of a deck (with replacement), what is the probability that you get at least 7 red cards?
a)
0.39
b)
0.61
c)
0.19
d)
0.81
6.
You are bored in Miss Soldan’s class, so you pass the time by flipping a coin 100 times. What is the probability that you get more than 51 tails?
a)
0.38
b)
0.62
c)
0.46
d)
0.54
7.
You trick Miss Soldan into playing for the juniors in the Powder Puff football game. As a quarterback, she typically completes 3% of her passes. If she makes 25 passes in the game, what is the probability that she will complete at least 3?
a)
0.04
b)
0.96
c)
0.01
d)
0.99
8.
You notice that cold weather makes Dr. Marks extra salty. When the weather is cold, there is a 40% chance of a tardy sweep. If February has 19 cold days, what is the probability that Dr. Marks will call more than 5 tardy sweeps?
a)
0.84
b)
0.16
c)
0.93
d)
0.07
9.
It is a little known fact that Miss Wanda is a world-famous poker player in her spare time. If she draws 8 cards out of a deck (with replacement), what is the probability that she gets 3 or more spades?
a)
0.32
b)
0.68
c)
0.11
d)
0.89
10.
You accidentally marry a Duggar (from 19 Kids and Counting). At the wedding reception, you are informed that you are expected to have 15 children. What is the probability that you will have 8 or more girls?
a)
0.50
b)
0.49
c)
0.30
d)
0.70
11.
Billy Bob is back on the Maury show to find out if he is the father of some children. There is a 40% chance that he is the father of any given child. If there are 11 children on this episode, what is the probability that he is the father of at least 3?
a)
0.97
b)
0.03
c)
0.89
d)
0.11
12.
You are a terrible driver. Whenever you drive, there is a 70% chance that you will run over a pedestrian. If you go for a drive 15 times, what is the probability that you will run over 7 or more pedestrians?
a)
0.98
b)
0.02
c)
0.95
d)
0.05
13.
According to a recent survey, 35% of Americans think that Kanye West would make a good President. If 400 people vote in the election, what is the probability that 150 or more vote for Kanye West?
a)
0.16
b)
0.84
c)
0.14
d)
0.86
100 %
