Answer:
4/5
Explanation:
Probability calculates the likelihood of an event occurring. The likelihood of the event occurring lies between 0 and 1. It is zero if the event does not occur and 1 if the event occurs.
For example, the probability that it would rain on Friday is between o and 1. If it rains, a value of one is attached to the event. If it doesn't a value of zero is attached to the event.
probability that a student selected at random takes math or science = probability a student takes maths + probability a student takes science
probability a student takes maths = number of maths students / total number of students
probability a student takes science = number of science students / total number of students
(500 / 2000) + (1100 / 2000) = 1600/2000 = 4/5