The phone company Telstra have 2 mobile service plans on offer which both have the same amount of phone call, text message and internet data credit. Both plans have a contract length of 24 months and the monthly cost is payable in advance. The only difference between the two plans is that one is a:

- 'Bring Your Own' (BYO) mobile service plan, costing $50 per month. There is no phone included in this plan. The other plan is a:
- 'Bundled' mobile service plan that comes with the latest smart phone, costing $71 per month. This plan includes the latest smart phone.

Neither plan has any additional payments at the start or end.

The only difference between the plans is the phone, so what is the implied cost of the phone as a present value?

Assume that the discount rate is 2% per month given as an effective monthly rate, the same high interest rate on credit cards.

A student just won the lottery. She won $1 million in cash after tax. She is trying to calculate how much she can spend per month for the rest of her life. She assumes that she will live for another 60 years. She wants to withdraw equal amounts at the beginning of every month, starting right now.

All of the cash is currently sitting in a bank account which pays interest at a rate of 6% pa, given as an APR compounding per month. On her last withdrawal, she intends to have nothing left in her bank account. How much can she withdraw at the beginning of each month?

Your poor friend asks to borrow some money from you. He would like $1,000 now (t=0) and every year for the next 5 years, so there will be 6 payments of $**1,000** from t=0 to t=5 inclusive. In return he will pay you $**10,000** in seven years from now (t=7).

What is the net present value (NPV) of lending to your friend?

Assume that your friend will definitely pay you back so the loan is risk-free, and that the yield on risk-free government debt is **10**% pa, given as an effective annual rate.

You are promised **20** payments of $**100**, where the first payment is immediate (t=**0**) and the last is at the end of the 19th year (t=**19**). The effective annual discount rate is ##r##.

Which of the following equations does **NOT** give the correct present value of these 20 payments?

The phone company Optus have 2 mobile service plans on offer which both have the same amount of phone call, text message and internet data credit. Both plans have a contract length of **24** months and the monthly cost is payable in **advance**. The only difference between the two plans is that one is a:

- 'Bring Your Own' (BYO) mobile service plan, costing $
**80**per month. There is no phone included in this plan. The other plan is a: - 'Bundled' mobile service plan that comes with the latest smart phone, costing $
**100**per month. This plan includes the latest smart phone.

Neither plan has any additional payments at the start or end. Assume that the discount rate is **1**% per month given as an effective monthly rate.

The only difference between the plans is the phone, so what is the implied cost of the phone as a present value? Given that the latest smart phone actually costs $**600** to purchase outright from another retailer, should you commit to the BYO plan or the bundled plan?