If there are 1,000 students in the junior class and 800 students in the senior class, what is the probability of selecting a sibling pair?

To understand why the answer is D, let's break down the scenario involving probability and the composition of the classes.

You have a total of 1,000 students in the junior class and 800 students in the senior class, which gives a combined total of 1,800 students across both classes. A sibling pair would consist of one student from the junior class and one from the senior class. The probability of selecting a sibling pair is determined by the likelihood that a randomly selected student from one class has a sibling in the other class.

Assuming that for every student in the junior class, there is one corresponding sibling in the senior class, we have 1,000 potential sibling pairs since there are 1,000 juniors. For these pairs, selecting one from the junior class and one from the senior class creates a scenario with 1,000 “successful” outcomes out of the total number of paired combinations possible.

The total possible outcomes when selecting one student from the junior class and one from the senior class would be 1,000 (juniors) multiplied by 800 (seniors), which equals 800,000 combinations. The probability is then calculated as the number of successful outcomes (the number of junior-senior sibling