2) P(first black marble)= 3/7 second black marble - When you removed 1st one only 2 black marbles are left and altogether marbles that are left = 6 P(second black marble) = 2/6=1/3 P(2 black marbles without replacement) means black and black marbles without replacement. P(2 black marbles without replacement) =3/7*1/3=1/7
3) P(first black marble)= 3/7 When you put that black marble back, you got again<span>3 black marbles and 4 red marbles in a bag. So, </span> P(second black marble)= 3/7 P(2 black marbles with replacement)=3/7*3/7= 9/49<span>
