Question

A bag contains 6 pennies, 2 nickels, 4 dimes, and 4 quarters. Silvia removes one coin from the bag and then, without replacing it, removes a second coin. What is the probability that the first coin she chooses is a penny and the second coin is a dime?

Answer 1

first coin 6 pennies out of 16 coins so you write that as

6
-
16

Answer 2

second coin 4 dimes out of 15 coins (because you didn't put the first coin back in so there are only 15 now.)

4
-
15

Answer 3

Now multiply those

6 4
- x --
16 15

Answer 4

1) How many ways can the penny be picked?
2) How many coins have you left since the removal of the first?
3) How many ways can the dime then be picked?

after deducing 1) and 3) the total number of ways this combination could be formed is one multiplied by the other
The probability is then 1/total number of combinations

Answer 5

24
---
240

which reduces to
1
-
10

so 1 out of every 10 times this should happen.

Answer 6

thank you so much :)