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Coco flips a penny, a nickel, and a quarter. Each coin is fair (meaning that heads and tails are equally likely to come up). What is the probability that at least one of the coins comes up heads?

Enter your answer as a fraction in simplified form.

 Jan 16, 2018
edited by SmartMathMan  Jan 16, 2018

2+0 Answers

 #1
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The probability of getting NO heads =1/2^3 =0.125. Then the probability of getting at least 1 head is:

1 - 0.125 =0.875

 Jan 16, 2018
 #2
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Possible outcomes

 

P          N          Q

 

H        H           H

H        H           T

H        T           T 

T         T          T

T         T          H  

H        T           H

T        H           T

T        H           H

 

Note there is only one outcme with no heads....so...the probability of at least one head is :

 

7/8

 

 

cool cool cool

 Jan 16, 2018

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