You walk 2 miles in 1212 hour. at that rate, how long will it take you to walk 3 miles?

2 miles in 1212 hour, 1 mile = 1212/2 = 606 hours

so in 3 miles = 606 * 3 = 1,818 hours

3 miles in 1818 hours.

If you mean 2 miles in 12 hours, it would take you 18 hours to walk 3 miles.
But if you do mean 2 miles in 1212 hours it would take 1818 hours to walk 3 miles.