Stuart Hogg’s first half red card meant Scotland were always up against it and three tries from Wales before the break gave them a comfortable lead. Liam Williams opened the scoring in a man of the match display with George North and Jamie Roberts both crossing before the break.
The second half was all Wales as North and Roberts completed doubles while Taulupe Faletau and replacement scrum half Rhodri Williams finished off a seven try rout.
The victory erased memories of last Sunday’s defeat to England and means Wales can now travel to South Africa this summer on the back of a positive display.
“In this tournament we have been inconsistent but I thought the players responded – it was a good display today,” said Gatland.
“You have to be ruthless and I think we were ruthless. The sending off helped but we were 13-3 up at the time of the red card and I think we would have gone on to win the game. It was a good performance and we took our opportunities. For us to do that was pleasing and we are looking forward to the summer now.”
With Scotland a man light for most of the game, Wales had plenty of opportunities to attack and they did just that with Williams, North and Faletau at their free running best.
Gatland added: “In the last three years we have won 12 of our 15 Six Nations games and we’ve had a pretty good record. We have been inconsistent in this championship but we have finished on a high.
“The guys did really well – we had to earn the right to go wide and the forwards delivered on that. We’ll take a lot of confidence from that.”
With the Six Nations at an end, Wales can now focus on their upcoming clashes with the Springboks.
Gatland said: “For a small country like Wales with a small playing base, we are happy with where we are but we want to keep improving as a side.
“We have a big tour of South Africa coming up. We feel we get better the longer the tournament goes on and what’s pleasing is the way the players respond.
“For the players to do that as they did today was fantastic.”