Karin has 13 coins (2 quarters, 6 dimes, 4 nickels, and 1 penny) in a piggy bank. She turns the bank upside down and shakes the bank until a coin falls out puts itand the shakes until another coin falls out.What is the probability that the first coin is a nickel and the second coin is a quarter?

Respuesta :

As the events are independent, taking X as the event that the first coin is a nickel and Y the event that the second coin is a quarter. The probability is

[tex]P(X\text{ and Y)}=P(X)\cdot P(Y)[/tex]

So in this case we have that

[tex]P(X\text{ and Y)}=P(X)\cdot P(Y)=\frac{4}{13}\cdot\frac{2}{12}=\frac{8}{156}=\frac{2}{39}[/tex]