How many laps do you run in 500m?
You have to swim 20 laps of the pool in a 500 yard race. One lap
is considered one length of the pool, or 25 yards. In the 500, you
are allowed a counter. The counter sits at the far end of the pool
and shows you how many laps you have swum. The counter will show up
to the number 17, then on the 19th lap, he or she will show a red
sign.