You are a contractor and charge $45 for a site visit plus an additional $24 per hour for each hour you spend working at the site. Write and solve an equation to determine how many total hours you have to earn $810 working at two separate work sites

Scores on a university exam are normally distributed with a mean of 78 and a standard deviation of 8. the professor teaching the class declares that a score of 70 or higher is required for a grade of at least “c.” using the 68-95-99.7 rule, what percentage of students failed to earn a grade of at least “c”?