Question

If only 4 out of every 10 eighteen-year olds vote on election day, how many eighteen year-olds will not be voting on election day in DC if there are a total of 20,000 eighteen year olds in DC?

Answer 1

Let

x ------> eighteen year-olds will be voting on election day

y ------> total of eighteen year-olds

we know that

x/y=4/10

x=(4/10)y -------> equation A

In this problem we have

y=20,000

find the value of x

x=(4/10)20,000

x=8,000

But remember that x is eighteen year-olds will be voting on election day

so

To find out how many eighteen year-olds will not be voting on election day

subtract from the total

20,000-8,000=12,000

the answer is 12,000