If Kia wins a prize, there is a 3/15 chance of getting a toy car when he first gets a prize. This is because there are 3 cars and a total of 15 prizes. This fraction can be reduced to 1/5.
After this, there will be one less car and one less prize total. So if he draws another prize, there will be a 2/14 = 1/7 chance of drawing a toy car.
We multiply these two fractions together to get our answer. 1/7 * 1/5 = 1/35, so B is the correct answer.
