YEAR 10 PROJECT BUSINESS MATHS

Christine Lugtu

1. Your wage is $70,000 per annum from which you pay tax; calculate the tax to the nearest dollar.

2. After Subtracting the tax from your wage, calculate your monthly take home wage.

Tax Subdivision % tax payable (marginal rate)

1 0 - 6,000 Nil

2 6,001 - 35,000 15c for each $1 over $6,000

3 35,000 - 80,000 $4,350 plus 30c for each $1 over $35,000

4 80,001 - 180,000 $17,850 plus 40c for each $1 over $80,000

70,000 – 35,000 = 35,00035,000 x 0.3 = 10,500

10,500 + 4,350 = $14,850

Tax = $14,850

70,000 – 14,850 = 55,150 55,150 ÷ 12 = 4,595.83

Monthly take home wage = $4,595.83

3. You purchased a motor bike for $5,000 and sold it for $4,000. Did you make profit or loss?

How much profit or loss you made in percentage?

5.000 – 4,000 = 1,000 loss

1000 x 100 = 20%

5000

20% of loss

4. Assume that 8% of your annual income is $4,000, what is your actual annual income?

4,000 x 8 = $320

100

Actual annual income = $320

5. Find out the house price and set up a loan over 25 years and make monthly payments on this loan. Assume the current interest rate is 5% per annum compounding monthly. Calculate the money owed

after 25 years.

House price = $250,000

Monthly compounding rate = 5 = 0.42

12

P = 250,000

R = 0.42

T = 25 years / 300 months

Money owed after 25 years = $879032.88

$879032.88

6. Purchase a car on hire purchase without a deposit. For convenience make monthly repayments for 3 years at 8% rate of interest per annum at simple interest. What would be the monthly repayment?

Car price = $45,000

P = 45,000

R= 8

T= 3 years / 36 months

PRT

100

= 45000 x 8 x 36

100

= 10800 ÷ 12

= $900

Monthly repayment = $900

7. You planned to invest $8500 in a term deposit. You had two investment plans from which to choose:

Plan 1: Simple interest at 5% per annum

Plan 2: Compound interest at 5% per annum compounding every six months

a) Calculate the total interest earned if you invested your money using Plan 1 for a year.

b) Calculate to the nearest cent, total interest earned if you invested your money using plan 2 for one year.

Total interest earned

Total interest earned

c) Calculate the simple interest rate that would provide the same total interest as earned under plan 2 for an investment of $8500 for a year. Give your answer correct to two decimal places.

= 0.06 + 5

= 5.06

PRT 100

5.06 x 8500 x 1

100

$430.10