I'm stuck trying to solve a really-existing problem regarding a redistribution of funds. Any help would be greatly appreciated.
A married couple decided to file taxes this year separately instead of jointly. Suppose Spouse A, by filing separating, receives a tax return of \$1,000. Spouse B, on the other hand, has to pay the government \$300. Their "joint" return is therefore \$700. The couple, however, regretted filing separately, and now needs to know how to equitably redistribute the return from Spouse A to Spouse B. Specifically, they want to know how much Spouse A has to pay Spouse B if the joint return were to be divided evenly between the two parties (as if they had filed jointly in the first place). The answer cannot be \$350 since that implies Spouse A netted \$1000 - \$350 = \$650, while Spouse B receives \$50 (i.e., \$350 - \$300). How do you determine the correct allocation?