Answer:
The probability is 3/95
Step-by-step explanation:
Okay this is a probability without replacement question.
Firstly we calculate the total number of coins = 7 + 9 + 4 = 20 coins
The probability that the first coin will be a dimes = number of dimes/total number of coins = 4/20 = 1/5
Now she removes a coin without replacement, if it was a dime, total number of coins becomes 19 and the total number of dimes becomes 3; Thus the probability of the second coins being a dimes = 3/19
Thus, the probability of both coins being dimes = probability of first coin being dimes * probability of second coins being dimes
= 1/5 * 3/19 = 3/95
