Bunuel wrote:
In a certain town, the ratio of the number of rented residences to the number of owned residences is 7:4. Those are the only two kinds of residences in this town. If there are 150 more rented than owned residences in this town, what is the total number of residences in the town?
A. 200
B. 350
C. 550
D. 700
E. 1100
Here
\(\frac{Rent}{owned} = \frac{R}{O} = \frac{7}{4}\) (Let R= rent and O = owned)
but Rent = owned + 150
therefore the fraction can be written as = \(\frac{{O+150}}{0} = \frac{7}{4}\)
or O = 200
substituting the value of O we get R = 350.
therefore total = rent + owned = 550