I don't know how to do these questions. Please help

Question

1. You want to have $100,000 when you retire in 15 years. If you can earn 4% interest compounded monthly, how much would you need to deposit now into the account to reach your retirement goal?
2. You want to have $200,000 when you retire in 30 years. If you can earn 3% interest compounded weekly, how much would you need to deposit now into the account to reach your retirement goal?
3. You want to have $300,000 when you retire in 20 years. If you can earn 9% interest compounded continuously, how much would you need to deposit now into the account to reach your retirement goal?
4. You want to have $200,000 when you retire in 30 years. If you can earn 4% interest compounded continuously, how much would you need to deposit now into the account to reach your retirement goal?

Answer 1

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