Question

1) There are two more assignments in your course before the semester ends, and if you get an A on at least one of them, you will get an A for the semester. Your "what-if" scenario looks like this: Event Probability A on paper and A on presentation .25 A on paper only .10 A on presentation only .30 Do not get an A on either .35 Answer the following questions: (1 point each, except the last item, 2 points) 1a) What is the probability of getting an A on the paper?

Answer 1

The probability of getting an A on the paper is 0.35.

Explanation:

The events of getting an A on the paper and presentation can be defined as follows:

X = Event of getting an A on the paper.

Y = Event of getting an A on the presentation.

The probabilities of these events are:

P (Only X) = 0.10

P (Only Y) = 0.30

P (X ∩ Y) = 0.25

Consider the Venn diagram below.

According to the Venn diagram the probability of getting an A in the paper, i.e. P (X), can be computed as:

P (X) = P (Only X) + P (X ∩ Y)

Compute the probability of X as follows:

`P (X) = P (Only\ X) + P (X \cap Y)\\=0.10+0.25\\=0.35`

Thus, the probability of getting an A on the paper is 0.35.