Answer:
Explanation:
The total number of coins in the jar is 7 + 6 + 8 = 21.
To find the probability that the sum of the values of the selected coins is 10 cents, we need to count the number of ways that we can select 2 coins such that their total value is 10 cents.
There are two ways to select two coins that have a total value of 10 cents:
Select a nickel and a dime.
Select two pennies.
The probability of selecting a nickel and a dime is (6/21) * (8/20) = 0.08, where 6/21 is the probability of selecting a nickel on the first draw, and 8/20 is the probability of selecting a dime on the second draw (without replacement).
The probability of selecting two pennies is (7/21) * (6/20) = 0.105, where 7/21 is the probability of selecting a penny on the first draw, and 6/20 is the probability of selecting a penny on the second draw (without replacement).
Therefore, the probability that the sum of the values of the selected coins is 10 cents is:
P(X = 10) = 0.08 + 0.105 = 0.185
To find the probability that the sum of the values of the selected coins is 11 cents, we need to count the number of ways that we can select 2 coins such that their total value is 11 cents.
There is only one way to select two coins that have a total value of 11 cents:
Select a nickel and a penny.
The probability of selecting a nickel and a penny is (6/21) * (7/20) = 0.07, where 6/21 is the probability of selecting a nickel on the first draw, and 7/20 is the probability of selecting a penny on the second draw (without replacement).
Therefore, the probability that the sum of the values of the selected coins is 11 cents is:
P(X = 11) = 0.07