P(green 3 consecutive times)

[nycmath]

A bag has 20 green marbles, 15 blue marbles and 25 red marbles. What is the probability of randomly selecting a green marble three consecutive times?

[Eigenvalue]

With replacement
[tex]\frac{20}{60}[/tex]*[tex]\frac{19}{59}[/tex]*[tex]\frac{18}{58}[/tex]

=[tex]\frac{19*18}{3*2*29*59}[/tex]

=[tex]\frac{57}{1711}[/tex]

Without replacement:
[tex]\frac{20}{60}[/tex]*[tex]\frac{19}{60}[/tex]*[tex]\frac{18}{20}[/tex]

=[tex]\frac{19*9}{10*60*3}[/tex]

=[tex]\frac{57}{200}[/tex]

[nycmath]

With replacement
[tex]\frac{20}{60}[/tex]*[tex]\frac{19}{59}[/tex]*[tex]\frac{18}{58}[/tex]

=[tex]\frac{19*18}{3*2*29*59}[/tex]

=[tex]\frac{57}{1711}[/tex]

Without replacement:
[tex]\frac{20}{60}[/tex]*[tex]\frac{19}{60}[/tex]*[tex]\frac{18}{20}[/tex]

=[tex]\frac{19*9}{10*60*3}[/tex]

=[tex]\frac{57}{200}[/tex]

This is a good mechanical reply but you don't explain what information in the word problem led to the right setup to find the correct answer.