Students at university x must have one of four class ranks – freshman, sophomore, junior, or senior. at university x, 35% of the students are freshman and 30% are sophomores. if a university x student is selected at random, the probability that he or she is either a junior or senior isa. 0.35b. 0.65c. 0.70d. 0.895

A. 0.35

Step-by-step explanation:

Given that there are four class ranks – freshman, sophomore, junior, or senior

Freshman = 35% = 0.35

Sophomore = 30% = 0.3

Junior or senior = 100% - 35% - 30%

                          = 1 - 0.35 - 0.30

                          = 0.35

The probability that a student selected at random is either a junior or senior is 0.35.

B. 2x + 9y = 18

Step-by-step explanation: