Q.3 A high-quality insulation doubles the cost of a traditional insulation (assume $X), which is fully loaned for q years with an annual interest rate of m (in %). This results in an annual energy saving of n (in %) (assume the total annual energy cost is $Y). Assume the average monthly energy cost growth rate is p (in %). Please derive the equation to determine the month when the energy saving is over the extra loan payment due to the use of high-quality insulation. Calculate the number if X=100,000, Y=20,000, m=8%, n=3%, p=0.4%, q=30.

Calculate the future value if present value (PV) = $1548,  interest rate (r) = 9.0% and number of years (t) = 18

Before last year, Ellie (Luke's wife) taught music and earned $30,400. She also earned $9,600 by renting out their basement as a studio apartment. Ellie saves every month. At the end of a typical year she would have saved a total of 10% from her wages and the income earned from the basement for the entire year, and earned a total of 0.5% in interest (for the entire year). At the beginning of last year, Ellie stopped teaching music. She also stopped renting out their basement, and began to use it as the office for her new web design business. The balance on her savings account was $150,000, and she took $5,000 from this account to buy a new laptop computer and a new printer (which also functions as a scanner and a facsimile). She also borrowed $12,000 from the local bank to purchase additional machinery and equipment (a graphics tablet, desktop computer, studio camera and an external hard drive). Her loan payment is $250 per month. During last year, she paid $3,000 for the lease of a…

Which statement is true? a) An arithmetic gradient sits atop a present worth b) An arithmetic gradient increases or decreases by a constant percentage over time c) The Future worth of an annuity is one time period to the right of the last arrow d) All of the above e) None of the above