Mai and Elena are shopping for back-to-school clothes. They found a skirt that originally cost \$30 on a 15%-off sale rack. Today, the store is offering an additional 15% off. To find the new price of the skirt, in dollars, Mai says they need to calculate \(30\boldcdot 0.85\boldcdot 0.85\). Elena says they can just multiply \(30\boldcdot 0.70\).

1. How much will the skirt cost using Mai’s method?
2. How much will the skirt cost using Elena’s method?
3. Explain why the expressions used by Mai and Elena give different prices for the skirt. Which method is correct?

Technology required. One \$1,000 loan charges 5% interest at the end of each year, while a second loan charges 8% interest at the end of each year.

1. Complete the table with the balances for each loan. Assume that no payments are made and that the interest applies to the entire loan balance, including any previous interest charges.
2. Which loan balance grows more quickly? How will this be visible in the graphs of the two loan balances, \(b\) and \(c\) as functions of the number of years, \(t\)?
3. Use technology to create graphs representing \(b\) and \(c\), over time. The graph should show the starting balance of each loan as well as the amount of the loan after 15 years. Write down the graphing window needed to show these points.

Lin opened a savings account that pays \(5\frac{1}{4}\%\) interest annually, and she deposited \$5,000.

If she makes no deposits and no withdrawals for 3 years, how much money will be in her account?

A person lends his friend \$500. They agree to an annual interest rate of 5%.

Write an expression for computing the amount owed on the loan, in dollars, after \(t\) years if no payments are made.

Select all situations that are accurately described by the expression \(15 \boldcdot 3^5\).

The real estate tax rate in 2018 in a small rural county increased by \(\frac{1}{4}\%\). In 2017, a family paid $1,200.

Which expression represents the real estate tax, in dollars, that the family will pay in 2018?