Directions: Using the digits 1-9 at most one time each, find the closest sum to 10,000 using two 4-digit addends.

### Hint

Which digits will be the most helpful to focus on to make the solution as close to 10,000 as possible?

### Answer

10,000 = (6521+3479) or (5671+4329) or (5679+4321) & other mixes of the same numbers in different positions

Source: Jessica Goree