The ratio of the arc length to the circumference is the same as the measure of angle AOB in radians to 2pi. 2pi radians is a full circle. We can now construct an equation, with x being our answer.
First, we try to simplify both sides. Next, we multiply both sides by pi. Then, we multiply both sides by 2. Finally, our answer is 2, so 2 radians.
So the total number of marbles is 18(6+4+3+5) right? So we have 4 green and 3 blue marbles. So together we have 7 marbles that we want to get right? Now 7/18 is the chance that this will happen. So ans:7/18