Probabilities...........................

a student has 2yellow,1 orange, and 2 green folders that are the same size.the first folder he chooses at random is yellow.If the student keeps the first folder, what is the probability that the second folder he chooses at random is isalso yellow?

The original probabilities are determined by the number of "colour" folder divided by the total number of folders:
Let n = total number of folders = 5
y = number of yellow folders = 2
o = orange folders ... and so on.
Yellow = y/n = 2/5
Orange = o/n = 1/5
Green = g/n = 2/5

After choosing and keeping the yellow folder, the total number of folders become 4, the number of yellow folder is 1.
So, n=4 and y=1. Based on the formula above, what do you think the probability is?

so he has 2+1+2=5 folders with 2 being yellow
so on the second try there are four folders left with 1 being yellow
so that means getting the second folder has a 1/4 probability
or 25%

25%

1/4 of 25% I think