Question

In the state of indiana, 368,000 people lacked basic prose literacy skills. If this is 8% of the population of indiana residents aged 5 years and older, estimate the population of indiana residents aged 5 years and older.

Answer 1

This problem can be solved with a proportion. We know that 8% of the population is the 368,000 and we want to find the whole population.

To make the proportion, let P be the population. Left side of the equals is the group we know, right side is the whole state, the top is the portions, the bottom are the populations.

We can't have percents in the proportions, so let's convert them to fractions or decimals. Percent means "per 100". So 8% = 8 per 100 = 8 / 100 = 0.08  Similarly, 100% = 100 per 100 = 100/100 = 1

$\frac{0.08}{368000} =\frac{1}{P}$

Now we cross multiply to solve.

(0.08)(P) = (1)(368000)

0.08P = 368000

P = 368000/0.08    <-- divide both sides by 0.08

P = 4600000

Thus, Indiana has a population (that's aged 5 years or older) of 4,600,000.