i tried finding the answer by dividing the first to problems in half but i lost my way after that

Question

In Chicago, the tax on a property assessed at $520,000 is $7,280. If tax rates are proportional in this city, how much would the tax be on a property assessed at $280,000?

Answer 1

Another way of looking at the proportion problem is to use the method of finding

the constant of proportion...

 

(Assessed Value)k = Tax Amount

Where k is the constant of proportion.

 

Thus, we have:  520000k=7280

                        k = 7280/520000

                        k = .014

 

Thus, our formula for finding the tax is AV(.014)

 

For property with assessed value of $280,000 the tax=280000(.014) = $3,920

 

Answer 2

Starting with a division is correct. Just do two of them!

 

tax / assessment = tax / assessment

 

7280 / 520000 = tax / 280000           Multiply both sides by 280000

7280(280000) / 520000 = tax            Simplify numerator

2122400000 / 520000 = tax               Divide

4081.53846 ≈ tax

 

The tax is approximately $4,081.54.