The shaded section of the strip diagram represents the percent of the number of students that get more than 9 hours of sleep each night. Of the students surveyed, 80 get more than 9 hours of sleep each night. How many students were surveyed?

An office supply company conducted a survey before marketing a new paper shredder designed for home use. in the survey, 80 % of the people who tried the shredder were satisfied with it. because of this high satisfaction rate, the company decided to market the new shredder. assume that 80 % of all people are satisfied with this shredder. during a certain month, 100 customers bought this shredder. find the probability that of these 100 customers, the number who are satisfied is 69 or fewer.

Gabrielle's age is two times mikhail's age. the sum of their ages is 84. what is mikhail's age?

Xy x xy if a and b are positive integers such that a*b=9 and b*a=72 what is the value of a/b