3 of every 5 people actually voted.....that means 2 of every 5 didn't vote...so 3/5 of the total voters voted and 2/5 of the entire voters didn't vote.
so if there is 18000 voters.....then 3/5(18000) = 54000/5 = 10,800 people actually voted
now...the ones who favored a new park (pool ) ? ......
5 of every 8 favored a new pool....and 3 of every 8 didn't....so 5/8 of the total voters favored a new pool...
5/8(10,800) = 54,000/8 = 6750 people voted for the new pool <==