SOLUTION: Carol McHugh has 3 quarters, 4 dimes, and 2 nickels in her purse. she takes one coin out of her purse without looking. a) find the probability that carol has taken: (1) a quarte

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Question 1134218: Carol McHugh has 3 quarters, 4 dimes, and 2 nickels in her purse. she takes one coin out of her purse without looking.
a) find the probability that carol has taken: (1) a quarter; (2) a dime; (3) a nickel
b) show that the sum of the probabilities from part a is 1.
c) find the probability that the coin has taken is worth: (1) less than 25 cents; (2)less than 25 cents; (3) not more than 5 cents
I understand how to do both a and b, however, got stuck with c.1,2 and 3.
thanks for helping!

Found 2 solutions by Theo, Glaviolette:
Answer by Theo(13342) (Show Source):
You can put this solution on YOUR website!
i think part 3 will be something like this.

p(quarter) = 3/9
p(dime) = 4/9
p(nickel) = 2/9

total probability is 3/9 + 4/9 + 2/9 = 9/9 = 1.

you take one coin out.

the probability that it's value is greater than 25 cents is 0, since the highest value coin is 25 cents.

the probability that it's value is greater than or equal to 25 cents is 1/3 since only a quarter has a value greater than or equal to 25 cents.

the probability that it's value is less than 25 cents would be 4/9 + 2/9 = 6/9 since either a dime or a nickel would be worth less than 25 cents.

the probability that it is worth not more than 5 cents is 2/9 since only a nickel is not worth more than 5 cents.

probability of a quarter is 3/9.

probability of a dime or a nickel is 4/9 + 2/9 = 6/9.

probability of a nickel is 2/9.

a quarter is worth exactly 25 cents.

a dime or a nickel is worth less than 25 cents.

a nickel is worth exactly 5 cents.

that's what i think they are asking you.

Answer by Glaviolette(140) (Show Source):
You can put this solution on YOUR website!
The problems you put for c 1 and 2 are the same. I'm sure that's a type.