51.7k views
2 votes
Matt Bonner has 8 dimes, 9 pennies, and 4 quarters in his pocket. If each coin is equally likely to be pulled out of his pocket in order without replacement, what is the probability that he will pull out the 2 quarters in a row and then 2 pennies? ***There are 4 total draws!!!! *

32/7203
0.602%
0.89%
0.44%

User Panu Logic
by
4.6k points

2 Answers

3 votes

Answer:

0.602%

Explanation:

Total coins:

8+9+4 = 21

Quarter, Quarter, Penny, Penny:

4/21 × 3/20 × 9/19 × 8/18

4/665 × 100

0.6015037584%

User Alfia
by
4.1k points
2 votes

Answer:

B. 0.602%

Explanation:

Probability is essentially (# times specific event will occur) / (# times general event will occur). Here, we have a few specific events: draw a quarter, draw a second quarter, draw a penny, and draw another penny. The general event will just be the number of coins there are to choose from.

The probability that the first draw is a quarter will be 4 / (4 + 8 + 9) = 4/21.

Since we've drawn one now, there's only 21 - 1 = 20 total coins left. The probability of drawing a second quarter is: (4 - 1) / (21 - 1) = 3/20.

The probability of drawing a penny is: 9 / (20 - 1) = 9/19.

The probability of drawing a second penny is: (9 - 1) / (19 - 1) = 8/18.

Multiply these four probabilities together:

(4/21) * (3/20) * (9/19) * (8/18) = 864 / 143640 ≈ 0.602%

The answer is B.

User Max Mikhaylov
by
4.1k points