Trying to end a three-game skid, the 49ers flew to Qwest Field for an NFC West rematch with the Seattle Seahawks on Thursday night.  In the first quarter, the Niners started off bumpy as Seahawks RB Shaun Alexander got a 3-yard TD run for Seattle's early strike and the only score of the period.  In the second quarter, San Francisco would get a field goal before halftime as kicker Joe Nedney nailed one from 39 yards out.  After a scorless third quarter, the Niners were in full force as QB Alex Smith completed an 8-yard TD pass to rookie TE Vernon Davis.  Afterwards, Smith would complete a 20-yard TD pass to RB Frank Gore.  Then, the 49ers wrapped the game up with Smith getting a very easy 18-yard QB sneak for a touchdown.  Seattle would get one more score as QB Matt Hasselbeck completed a 22-yard TD pass to TE Jerramy Stevens.  Fortunately, the Niners would get the win and the season sweep over the Seahawks.  With the win, the 49ers improved to 6-8
Question: How many yards longer was the longest touchdown run than the shortest?
Answer: 15