It costs 30 dollars per month for a cell phone plus 10 dollars for every GB of data. Which expression can be used to represent the cost of a cell phone bill when x is the number of GB of data used?

30 + 10

30 + 10

30x + 10
30, x, + 10

10x + 30
10, x, + 30

10x + 30x

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.