Probabilities of At-Least

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%

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?

• 0.05
• 0.95
• 0.17
• 0.83

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

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?

• 0.74
• 0.26
• 0.57
• 0.43

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?

• 0.39
• 0.61
• 0.19
• 0.81

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?

• 0.38
• 0.62
• 0.46
• 0.54

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?

• 0.04
• 0.96
• 0.01
• 0.99

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?

• 0.84
• 0.16
• 0.93
• 0.07

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?

• 0.32
• 0.68
• 0.11
• 0.89

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?

• 0.50
• 0.49
• 0.30
• 0.70