Sum certain cells to reach target value

Does anyone know how I can manipulate a list with a formula to sum certain cells to reach a target value?

Okay, I know that question is confusing. Here is an example that may clear things up: I have a list of data in cells A1:A20 that totals $1,000,000. I'm looking for only the data that totals to $200,000. Can I write a formula that tells me which of the 20 cells, when added together, equal $200,000?

Thanks!