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The sum of two numbers is 12 and their difference is 18 what are the two numbers

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.

Acompany charges $0.10 for each letter engraved. bobby plans to spend no more than $5.00 on the engraving on a jewelry box. write and solve an inequality to find the maximum number of letters he can have engraved.