A few usually means three to five of something, so a few minutes is a little bit longer than a couple, however they are usually used in the same way.
You will probably hear this more often in older films and books, and sometimes as a joke.
So instead of simply saying the numbers that you see on the clock, by using the same phrases and terms that most English speakers do.
What do you need for your English tea? The leaders of the enemy, having reconnoitered the country by their scouts, select from the entire army sixty thousand men, belonging to those states, which bear the highest character for courage; they privately arrange among themselves what they wished to be done, and in what manner; they decide that the attack should take place when it should seem to be noon.