1. 1 Press Ctrl-A ©G Dear 2010 – Not to be sold/Free to use Fixed Interest Stage 6 - Year 12 General Mathematic

2. 2 SI = P r n also known as Simple Interest. Click on the letters for their meaning. S imple I nterest P rincipal Money ` umber of Periods R ate of Interest per period Don’t Delete It is calculated as a percentage of money borrowed. You must repay the principal and the interest.

3. 3 Mary borrowed $5000 for 4 years at 7% p.a. to buy some sheep. SI = P r n = 5000 x 7 100 x 4 = $1400 How much does she have to repay? Repay = $5000 + $1400 = $6400

4. 4 A chef need $20 000 at 9% p.a for 4 years to refurbish his restaurant. He has a 10% deposit. i) How much was the deposit? Deposit = 10 100 x 20 000 = $2000 ii) What is the balance borrowed? Balance = 20 000- 2 000= $18 000 iii) How much is the interest? Interest = 18 000 x 9 100 x 4= $6 480

5. 5 A chef need $20 000 at 9% p.a for 4 years to refurbish his restaurant. He has a 10% deposit. i) How much does he repay? Repay = 18 000 Borrowed + 6480 Interest = $24 480 ii) What is the monthly repayment? Monthly Repay = 24 480 Repay ÷ 4 Years ÷ 12 Months = $510 per month

6. 6 Jane borrowed $70 000 to open her detective agency. She repaid it at $933.33 per month for 10 years. What was her flat interest rate? Total Repayments = $933.33x 12 monthsx 10 years = $ 112 000 Total Interest = $112 000- $70 000= $42 000 Annual Interest = $42 000÷ 10= $4 200 Interest % = 4 200 70 000 x 100%= 6% p.a.