2.  Percentage problems are solved using proportions. › (100 - %) New 100 = Old › If you have a coupon that gives you a 15% discount on your groceries and your total bill was $155, what would it have cost you without the coupon?

3.  Mark-ups are the idea that stores charge more than they paid for a product in order to make a profit.  Use the same proportion as before except you add: › (100 + %) New 100 = Old WHY???

4.  A bookstore buys a book from the publisher for $71 and the store policy is to mark up all books 32% before putting them on the shelves for customers to purchase. How much should the bookstore charge for the book?

5.  Define your variable.  Set up the equation. A typical college student spends 1/3 of her waking time in class, 1/4 of her waking time eating, 1/12 of her waking time working out, 3 hours studying, and 2.5 hours doing other things. How many hours of sleep does the typical college student get?  Solve for the variable.  Answer the question asked!! 4x + 3x + x + 66 = 12x 8x + 66 = 12x 66 = 4x x = 16.5 7.5 hours of sleep

6.  Interest is money paid for the use of money.  Banks pay interest to you if you have a savings account of some kind because they are “using” your money.  You pay the bank interest when you borrow money from them to buy things.  Interest charges can get you in trouble!! If you get a credit card, always pay the total amount to avoid these charges!

7.  Simple Interest – › I = Prt  I is the interest charged (or earned)  P is the principal invested (or borrowed)  r is the interest rate expressed as a decimal  t is the time the money is invested in years  If you invest $1400 in a CD for 5 years at a rate of 3%, how much interest do you earn? › P = 1400r =.03t = 5 › I = (1400)(.03)(5) › I = $210  So, after 5 years you would have $1610!!!

8.  Sometimes, people split their money into different accounts to maximize their earning potential and minimize their risk. › Michael has $10,000 to invest. He put some of it in a CD that earns 2% per year and the rest in a money market account that earns 12% per year. If he earned $750 in interest after the first year, how much did he invest in each account? › Let x = the amount invested in the CD.  (x)(.02)(1) The interest earned on the CD.  (10000-x)(.12)(1) The interest earned on the money market account. .02x + 1200 -.12x = 750  1200 -.1x = 750  -.1x = -450  x = 4500  So, Michael invested $4500 in the CD and $5500 in the money market account.