so when you consider that one adult usually needs at least seventy-five thousand dollars a year to live on , if theyre going to have any hope for saving some of their income , then you can see that you have to consider that there are two adults in a marriage , which means that the cost for seventy-five thousand dollars a year doubles to make it one hundred and fifty thousand dollars a year in income thats needed just to support the two adults paycheck to paycheck .