Reuben wants to have an amount of $40,000.00 in 16 years' time when she retires. She can invest her money at a simple interest rate of 5.5% per annum. How much money ( to the nearest dollar) should she invest now to achieve her aim?

Asmall business produces and sells balls. the fixed costs are $20 and each ball costs $4.32 to produce. each ball sells for $8.32. write the equations for the total cost, c, and the revenue, r, then use the graphing method to determine how many balls must be sold to break even.