I tried using the NPV method I saw on another example and got 6,125, which was incorrect.

The following two cash flows Cash Flow (CF-1) and Cash Flow (CF-2) are economically equivalent. The effective interest rate is 6%% per period. The value of A (annuity of CF-1) is $3,000 and the value of B (cash flow in year 9 of CF-2) is $6,000. Please follow the questions to find out the unknown X. Round the answer to the nearest integer. Cash Flow (CF-1) 0 1 2 3 4 5 6 7 8 9 B Cash Flow (CF-2) X X/3 X/3 X/3 0 1 2 3 4 5 6 7 8 9