Cash Flow statement – Big time Co.

Dear Sir John.

Given below is the question on cash flow.
Big Time Co had the following transactions during the year.
· Purchases from suppliers were $18,500, of which $2,550 was unpaid at the year end. Brought forward payables were $1,000.
· Wages and salaries amounted to $9,500, of which $750 was unpaid at the year end. The financial statements for the previous year showed an accrual for wages and salaries of $1,500.
· Interest of $2,100 on a long term loan was paid in the year.
· Sales revenue was $33,400, including $900 receivables at the year end. Brought forward receivables were $400.
· Interest on cash deposits at the bank amounted to $175.
Using the direct method, what is Big Time Co’s cash flow from operating activities?

As per my calculation after considering accruals & other adjustment.

Sales -> 33400+400-900 = 32,900
wages paid -> 9500-750+1500 = (10,250)
purchase (18,500-2550+1000)
interest paid -> (2100)

However the interest received should be part of investing so should be excluded from operating activities. thereby I get the answer of 3600. which is wrong. I am stuck on this for a while can you please help me with this. Thank you.!