First, you have to know how many marbles there are, and if you count them all up there are 15 marbles in total. Next, there are 3 blue marbles, so you would put the fraction as 3/15, or simplified to 1/5. Now, if you don't replace that blue marble, you now only have 14 marbles, and there are 2 yellow, which means you have a 2/14 chance of drawing a yellow marble, simplified to 1/7. But because there are two parts of the problem you are going to multiply 1/5 by 1/7 to get 1/35, which is your answer.
4+3+2+6= 15-1= 14 if they get a blue marble aand dont put it back it would be one less and then you have fourteen and if you simpify it it would be 1/7
