So, i am pretty new at a subject called "applied mathematics in economics" so take me easy : d

i have this problem:

to provide for future education costs a family considers various methods of saving. assuming that the saving lasts 10 years at an interest rate of 7,5%/year
a) calculate the value of the fund after 10 years when a single deposit of 2000£ is made annualy
b) how much should be deposited each year if the final value is 4£
c) how much should be deposited each month if the final value is 4£

the only formula i know is sn = s₀*(1+i)ⁿ but i don't think that this is applicable here?

in advance and i am really sorry if it's very easy but i just don't understand

Leslie started last week with $1200 in her checking account. during the week, she wrote the checks below. trans typ./ check no. date description of transaction payment/ debit deposit/ credit (+) balance 1,200 00 324 10/6 miller's food market 45.87 45 87 groceries 1,154 13 325 10/7 cyber center computer outlet 218.59 218 59 monitor 935 54 326 10/9 sandy's beauty salon 30.00 30 00 haircut and styling 900 59 deposit 10/10 paycheck 621.33 621 33 1,621 92 evaluate leslie's check register. a. leslie did a good job. everything is correct. b. the final balance is wrong; she did not add everything correctly. c. leslie should have written debit instead of deposit for the transaction type. d. leslie switched the debit and credit columns.