if a tray contain 6 red socks and 4 blue socks . what is the probability that 2 socks , picked will be red

4 answers

2/15
Probability = P(2 red)+P(2 blue)
=6/10*5/9 + 4/10*3/9
=(30+12)/90
=7/15
Question asks P(2 red), so
Probability of first red=6/10
Probability of second red = (6-1)/(10-1)=5/9
By the multiplication rule,
P(2 red)
=6/10*5/9
=30/90
=1/3
6C2÷10C2 = 15÷45=(1÷3)=0.33333...