Giselle works as a carpenter and as a blacksmith. she earns $20 per hour as a carpenter and $25per hour as a carpenter and 30 hours, and earned a total of $690.how long did giselle work as a carpenter last week, and how long did she work as a blacksm

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.