ProfessorWilliamson counts his
Midterm as 2/3 of the grade and his final as 1/3 of the grade.
Wendy scored only 48 on the midterm. What range of
Scores on the final exam would put Wendy’s average
Between 70 and 79 inclusive?

Solve for two values of F to give the high and low scores that get the final grade to 70 and 79:

2/3 x 48 + 1/3 x F = 70
2/3 x 48 + 1/3 x F = 79

I think you'll find that Wendy is in trouble!

In 18 years, a family expects to need $86,000 for a child's college education. If they can invest at a rate of 6% per year, compounded monthly, how much do they need to deposit immediately to have sufficient funds 18 years from now?

The formula for the total money after compound interest is added is:

Sum = Principal \times \(1 + \frac{Rate}{100}\)^{time}

The interest is compounded annually, and you're given the time in years, so there is no problem here.

Sum = 86000
Principal = What you want to find
Rate = 6
time = 18

Can you post what you get? :)