Again sorry but I don't seem to be able to type in the writing box for some reason :S
Here's my question/ clues that were given with it:
A sum of $1900 is deposited today into an account earning interest at 9.9% p.a. convertible 2 times a year. What deposit should be made in 1 years time if the account is to accumulate to $5900 in 4 years from today?
(The deposit of $1900 accumulated for (2×4) time units plus the accumulation of $X for the appropriate number of time units will equal $5900.
As an example to check your method, suppose that $1,200 is deposited today into an account earning 10% p.a. convertible 4 times a year. What deposit should be made in 3 years time if the account is to accumulate to $5,000 in 4 years from today? The answer is $2,915.89)