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6.02 Annuities with interest factors

Worksheet
Reducible interest tables
1

The following financial table displays the monthly repayments on a \$1000 loan:

\text{Annual interest rate}10 \\ \text{years}15 \\ \text{years}20 \\ \text{years}25 \\ \text{years}30 \\ \text{years}
3\%9.666.915.554.744.22
4\%10.127.406.065.284.77
5\%10.617.916.605.855.37
6\%11.108.447.166.446.00
7\%11.618.997.757.076.65
8\%12.179.568.367.727.38

Calculate the monthly instalments required to pay off a 25-year loan of \$1000 at 4\% p.a. monthly reducible interest.

2

The following financial table displays the monthly repayments on a \$1000 loan:

\text{Annual interest rate}10 \\ \text{years}15 \\ \text{years}20 \\ \text{years}25 \\ \text{years}30 \\ \text{years}
4\%10.127.406.065.284.77
5\%10.617.916.605.855.37
6\%11.108.447.166.446.00
7\%11.618.997.757.076.65
8\%12.139.568.367.727.34
9\%12.6710.149.008.398.05

Calculate the monthly instalments required to repay each of the following loans:

a

A 25-year loan of \$1000 at 5\% p.a. monthly reducible interest.

b

A loan of \$50\,000 repaid in 15 years with 8\% p.a. monthly reducible interest.

c

A 25-year loan of \$170\,000 at 6\% p.a. monthly reducible interest.

3

The following financial table displays the monthly repayments on a \$1000 loan:

\text{Annual interest rate}10 \\ \text{years}15 \\ \text{years}20 \\ \text{years}25 \\ \text{years}30 \\ \text{years}
5\%10.617.916.605.855.37
6\%11.108.447.166.446.00
7\%11.618.997.757.076.65
8\%12.139.568.367.727.34
9\%12.6710.149.008.398.05
10\%13.2210.759.659.098.78

Calculate the monthly instalments required to pay off a 15-year loan of \$200\,000 at 7\% p.a. monthly reducible interest.

4

The following financial table displays the annual repayments on a \$1000 loan:

\text{Annual interest rate}10 \\ \text{years}15 \\ \text{years}20 \\ \text{years}25 \\ \text{years}30 \\ \text{years}
5\%129.5096.3480.2470.9565.05
6\%135.87102.9687.1878.2372.65
7\%142.38109.7994.3985.8180.59
8\%149.03116.83101.8593.6888.83
9\%155.82124.06109.55101.8197.34
10\%162.75131.47117.46110.17106.08

Calculate the annual installments needed to pay off a \$110\,000 home loan at 7\% p.a. reducible interest if the installments are to be paid in equal amounts over 15 years.

5

The following financial table displays the annual repayments on a \$1000 loan:

\text{Annual interest rate}20 \\ \text{years}25 \\ \text{years}30 \\ \text{years}35 \\ \text{years}40 \\ \text{years}
4\%73.5864.0157.8353.5850.52
5\%80.2470.9565.0561.0758.28
6\%87.1878.2372.6568.9766.46
7\%94.3985.8180.5977.2375.01
8\%101.8593.6888.8385.8083.86
9\%109.55101.8197.3494.6492.96

Calculate the annual instalments needed to pay off a \$160\,000 home loan at 6\% p.a. reducible interest if the instalments are to be paid in equal amounts over 25 years.

6

The following financial table displays the monthly repayments on a \$1000 loan:

\text{Annual interest rate}5 \\ \text{years}10 \\ \text{years}15 \\ \text{years}20 \\ \text{years}25 \\ \text{years}
3\%17.979.666.915.554.74
4\%18.4210.127.406.065.28
5\%18.8710.617.916.605.85
6\%19.3311.108.447.166.44
7\%19.8011.618.997.757.07
8\%20.2812.139.568.367.72

Amelia received a 5-year \$120\,000 loan at 3\% p.a. monthly reducible interest.

Using the financial table, calculate:

a

The amount of each monthly instalment.

b

The total repayments.

c

The interest on the loan.

d

The total interest as a percentage of the principal loan, correct to two decimal places.

7

The following financial table displays the monthly repayments on a \$1000 loan:

\text{Annual interest rate}5 \\ \text{years}10 \\ \text{years}15 \\ \text{years}20 \\ \text{years}25 \\ \text{years}
4\%18.4210.127.406.065.28
5\%18.8710.617.916.605.85
6\%19.3311.108.447.166.44
7\%19.8011.618.997.757.07
8\%20.2812.139.568.367.72
9\%20.7612.6710.149.008.39

Sally received a 5-year \$170\,000 loan at 4\% p.a. monthly reducible interest.

Using the financial table, calculate:

a

The amount of each monthly instalment.

b

The total repayments.

c

The interest on the loan.

d

The total interest as a percentage of the principal loan, correct to two decimal places.

8

The following financial table displays the monthly repayments on a \$1000 loan:

\text{Annual interest rate}5 \\ \text{years}10 \\ \text{years}15 \\ \text{years}20 \\ \text{years}25 \\ \text{years}
4\%18.4210.127.406.065.28
5\%18.8710.617.916.605.85
6\%19.3311.108.447.166.44
7\%19.8011.618.997.757.07
8\%20.2812.139.568.367.72
9\%20.7612.6710.149.008.39

Luke received a 5-year loan at 4\% p.a. monthly reducible interest. His total repayments were \$221\,040.

a

Calculate the amount of each monthly instalment.

b

Find the amount of the loan.

9

The following financial table displays the monthly repayments on a \$1000 loan:

\text{Annual interest rate}10 \\ \text{years}15 \\ \text{years}20 \\ \text{years}25 \\ \text{years}30 \\ \text{years}
4\%10.127.406.065.284.77
5\%10.617.916.605.855.37
6\%11.108.447.166.446.00
7\%11.618.997.757.076.65
8\%12.139.568.367.727.34
9\%12.6710.149.008.398.05

Dave received a 10-year loan at 4\% p.a. monthly reducible interest. His total repayments were \$170\,016.

a

Calculate the amount of each monthly instalment.

b

Find the amount of the loan.

10

The following financial table displays the monthly repayments on a \$1000 loan:

\text{Annual interest rate}20 \\ \text{years}25 \\ \text{years}30 \\ \text{years}35 \\ \text{years}40 \\ \text{years}
3\%5.554.744.223.853.58
4\%6.065.284.774.434.18
5\%6.605.855.375.054.82
6\%7.166.446.005.705.50
7\%7.757.076.656.396.21
8\%8.367.727.347.106.95

Han received a 25-year \$71\,000 loan at 5\% p.a. monthly reducible interest. If the term of the loan was reduced to 20 years, calculate:

a

The size of the monthly instalment when the term of the loan is 25 years.

b

The total amount repaid over 25 years.

c

The interest paid over 25 years.

d

The total amount repaid over a reduced term of 20 years.

e

The interest paid over the 20-year term.

f

The interest saved from a 5-year reduction in the term of the loan.

11

The following financial table displays the monthly repayments on a \$1000 loan:

\text{Annual interest rate}20 \\ \text{years}25 \\ \text{years}30 \\ \text{years}35 \\ \text{years}40 \\ \text{years}
2\%5.064.243.703.313.03
3\%5.554.744.223.853.58
4\%6.065.284.774.434.18
5\%6.605.855.375.054.82
6\%7.166.446.005.705.50
7\%7.757.076.656.396.21

Vaughn recieved a 25-year \$164\,000 loan at 4\% p.a. monthly reducible interest. If the term of the loan was reduced to 20 years, calculate:

a

The size of the monthly instalment when the term of the loan is 25 years.

b

The total amount repaid over 25 years.

c

The interest paid over 25 years.

d

The total amount repaid over a reduced term of 20 years.

e

The interest paid over the 20 year term.

f

The interest saved from a 5 year reduction in the term of the loan.

12

The following financial table displays the monthly repayments on a \$1000 loan:

\text{Annual interest rate}15 \\ \text{years}20 \\ \text{years}25 \\ \text{years}30 \\ \text{years}35 \\ \text{years}
2\%6.445.064.243.703.31
3\%6.915.554.744.223.85
4\%7.406.065.284.774.43
5\%7.916.605.855.375.05
6\%8.447.166.446.005.70
7\%8.997.757.076.656.39

Mae received a 30-year \$89\,000 loan at 2\% p.a. monthly reducible interest. If the term of the loan was reduced to 25 years, calculate:

a

The amount of each monthly instalment over a 30-year term.

b

The monthly instalment needed for a 25-year term.

c

The amount saved, from this 5-year reduction in the term of the loan.

13

The following financial table displays the monthly instalments required to repay \$1000:

\text{Annual interest rate}15 \\ \text{years}20 \\ \text{years}25 \\ \text{years}30 \\ \text{years}35 \\ \text{years}
5\%7.916.605.855.375.05
6\%8.447.166.446.005.70
7\%8.997.757.076.656.39
8\%9.568.367.727.347.10
9\%10.149.008.398.057.84
10\%10.759.659.098.788.60

Graziano received a 30-year \$80\,000 loan at 5\% p.a. monthly reducible interest. If the term of the other loan was reduced to 25 years, calculate:

a

The amount of each monthly instalment over a 30 year term.

b

The monthly instalment needed for a 25 year term.

c

The amount saved, from this 5 year reduction in the term of the loan.

14

The following financial table displays the monthly repayments on a \$1000 loan:

\text{Annual interest rate}10 \\ \text{years}15 \\ \text{years}20 \\ \text{years}25 \\ \text{years}30 \\ \text{years}
4\%10.127.406.065.284.77
5\%10.617.916.605.855.37
6\%11.108.447.166.446.00
7\%11.618.997.757.076.65
8\%12.139.568.367.727.34
9\%12.6710.149.008.398.05

Neil received a 10-year \$130\,000 loan at 6\% p.a. monthly reducible interest. If the interest rate was increased to 7\% p.a., find the increase in the total repayments needed to clear the debt.

15

The following financial table displays the monthly repayments on a \$1000 loan:

\text{Annual interest rate}15 \\ \text{years}20 \\ \text{years}25 \\ \text{years}30 \\ \text{years}35 \\ \text{years}
3\%6.915.554.744.223.85
4\%7.406.065.284.774.43
5\%7.916.605.855.375.05
6\%8.447.166.446.005.70
7\%8.997.757.076.656.39
8\%9.568.367.727.347.10

James received a 15-year \$110\,000 loan at 5\% p.a. monthly reducible interest. If the interest rate was increased to 6\% p.a., find the increase in the total repayments needed to clear the debt.

16

The following financial table displays the monthly repayments on a \$1000 loan:

\text{Annual interest rate}15 \\ \text{years}20 \\ \text{years}25 \\ \text{years}30 \\ \text{years}35 \\ \text{years}
3\%6.915.554.744.223.85
4\%7.406.065.284.774.43
5\%7.916.605.855.375.05
6\%8.447.166.446.005.70
7\%8.997.757.076.656.39
8\%9.568.367.727.347.10

Liza received a 15-year \$60\,000 loan at 6\% p.a. monthly reducible interest. If the interest rate fell to 5\% p.a., find the decrease in the total repayments needed to clear the debt.

17

The following financial table displays the monthly repayments on a \$1000 loan:

\text{Annual interest rate}15 \\ \text{years}20 \\ \text{years}25 \\ \text{years}30 \\ \text{years}35 \\ \text{years}
4\%7.406.065.284.774.43
5\%7.916.605.855.375.05
6\%8.447.166.446.005.70
7\%8.997.757.076.656.39
8\%9.568.367.727.347.10
9\%10.149.008.398.057.84

Delila received a 15-year \$60\,000 loan at 7\% p.a. monthly reducible interest. If the interest rate was fell to 6\% p.a., find the decrease in the total repayments needed to clear the debt.

18

Valentina is deciding between two \$109\,000 home loans. She has the capacity to pay \$3400 per month.

  • Option 1: 3.2\% p.a. over 3 years with fixed monthly repayments of \$3179.

  • Option 2: 2.6\% p.a. over 3 years with minimum monthly repayments of \$3151 that enables paying more than the minimum monthly repayment

a

What is the total repayment she will have to make with Option 1?

b

What is the maximum total repayment she will have to make with Option 2?

c

Which loan will cost less?

19

Elvira is deciding between two \$177\,000 home loans. She has the capacity to pay \$4600 per month.

  • Option 1: 4.8\% p.a. over 4 years with fixed monthly repayments of \$4060.

  • Option 2: 4.4\% p.a. over 4 years with minimum monthly repayments of \$4028 that enables paying more than the minimum monthly repayment.

a

What is the total repayment she will have to make with Option 1?

b

What is the maximum total repayment she will have to make with Option 2?

c

Which loan will cost less?

Interest tables with savings
20

The following financial table displays the monthly instalments required to save \$1000:

\text{Annual interest rate}5 \\ \text{years}10 \\ \text{years}15 \\ \text{years}20 \\ \text{years}25 \\ \text{years}
1\%16.267.935.153.772.94
2\%15.867.534.773.392.57
3\%15.477.164.413.052.24
4\%15.086.794.062.731.95
5\%14.706.443.742.431.68
6\%14.336.103.442.161.44
a

Calculate the monthly instalments required to save \$50\,000 in 15 years if the savings account earns 3\% interest per annum, compounded monthly.

b

Alana is going to start making regular monthly deposits into a savings account that earns 2\% interest p.a. If she plans to save \$20\,000 in 15 years, calculate:

i

The monthly instalments required to achieve her savings goal.

ii

The total amount she deposits to reach her savings goal.

iii

The interest she will earn over the 15-year period.

21

The following financial table displays the monthly instalments required to save \$1000:

\text{Annual interest rate}10 \\ \text{years}15 \\ \text{years}20 \\ \text{years}25 \\ \text{years}30 \\ \text{years}
3\%7.164.413.052.241.72
4\%6.794.062.731.951.44
5\%6.443.742.431.681.20
6\%6.103.442.161.441.00
7\%5.783.151.921.230.82
8\%5.472.891.701.050.67

The interest rate on a savings account is 4\% per annum, compounded monthly. Vincent can afford to save \$300 per month. How long will it take him to save \$143\,000?

22

The following financial table displays the monthly instalments required to save \$1000:

\text{Annual interest rate}15 \\ \text{years}20 \\ \text{years}25 \\ \text{years}30 \\ \text{years}35 \\ \text{years}
1\%5.153.772.942.381.99
2\%4.773.392.572.031.65
3\%4.413.052.241.721.35
4\%4.062.731.951.441.09
5\%3.742.431.681.200.88
6\%3.442.161.441.000.70
a

Calculate the monthly instalments required to save \$110\,000 in 30 years if the savings account earns 5\% interest per annum, compounded monthly.

b

If instead of making consistent payments to an annuity, a single deposit was made into the same account at the start of the investment, how much must be invested in order to end up with \$110\,000 after 30 years?

23

Mario made consistent monthly contributions to an annuity, and it was worth \$400\,000 after 25 years. His annuity earned 2\% interest per year, compounded monthly.

Georgia made a single large payment when Mario made his first monthly contribution, and her investment earned the same amount of interest with the same compounding periods. Her investment was also worth \$400\,000 after 25 years.

Find the value of the single payment that Georgia made.

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MS2-12-5

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