Property in dry gultch county is assessed at $305,000,000. the taxes to be raised are $13,750,000. what is the tax rate?

Well you know that the value is 305 million
And the taxes are 13.75 million. taxes are a percentage of the value. to get a percentage of the value you use :
value * percent = percentage of value

So:
305 million * percent = 13.75 million
or:
305 * x = 13.75
x = 13.75 / 305
x = .045

x = 4.5%

(13,750,000) / (305,000,000) =  0.04508  or 4.508 %