You roll a fair standard sided die. You have two options: keep or roll again. If you decide to keep, you receive a payout equal to the upface (in dollars). Otherwise, you can roll again. If the sum of your two rolls is at least , you pay a sum equal to the upface of your first roll (in dollars). If the sum of the two rolls is less than , you receive the upface of your second roll (in dollars). Assuming optimal play, what is your expected payout?