Two students are going to the store to buy school supplies. one student buys 2 packs of pencils and 3 packs of pens for $8.25. her friend buys 5 packs of pencils and 2 packs of pens for $11.00. is there enough information to determine the cost of one pack of pencils and one pack of pens? if so, find the cost of each.

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.