A sum of $3310 is to be paid back in 3 equal installments.

[email protected] wrote:A sum of $3310 is to be paid back in 3 equal installments. How much is each installment if the interest is compounded annually at 10% per annum.

It is not mentioned whether the installments are monthly or annual. But looking at the options, I think it should be yearly. Now, let us assume each installment will be I.

After 1st year, amount to be paid back = 3310*(1 + 10/100) - P = 3310*(1.1) - P = 3641 - P

After 2nd year, amount to be paid back = (3641 - P)*(1 + 10/100) - P = (3641 - P)*(1.1) - P ≈ 4000 - 2.1P

After 3rd year, amount to be paid back = (4000 - 2.1P)*(1 + 10/100) - P = (4000 - 2.1P)*(1.1) - P = 4400 - 3.31P

Now, after the 3rd year, there shouldn't be any amount left to be paid back.
So, 4400 - 3.31P = 0
--> P = 4400/3.31 ≈ 4400/3.3 = 44000/33 = 4000/3 ≈ 1333 ≈ 1331

The correct answer is B.