How to do doubles plus one and double minus one

Danielle earns a 7.25% commission on everything she sells at the electronics store where she works. she also earns a base salary of $750 per week. what were her sales last week if her total earnings for the week were $1,076.25?

How do you find the distance of each number from the mean

The daily production of a company is modeled by the function p = -w^2 + 75w - 1200. the daily production, p, is dependent on the number of workers (w) present. if the break-even point is when p=0, what are the least and greatest number of workers the company must have present each day in order to break even? 50 points! will give brainliest!