Answer :
Of the 10 marbles in the container, 5 are green. So if Aileen doesn't peek,
her chance of drawing a green marble is 5/10 or 0.5 .
The chance that she will draw a green marble the first time is 0.5 .
The chance that she will draw a green marble the second time is 0.5 .
The probability that she will draw a green marble both times is
(0.5) x (0.5) = 0.25 or 25 percent .