SOLUTION: A city has 3200 houses out of which 3/4 are older than 100 years. if 1/3 of these old houses are renovated and an additional 800 new houses were built, what is the percentage of h

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: A city has 3200 houses out of which 3/4 are older than 100 years. if 1/3 of these old houses are renovated and an additional 800 new houses were built, what is the percentage of h      Log On


   

Question 1044426: A city has 3200 houses out of which 3/4 are older than 100 years. if 1/3 of these old houses are renovated and an additional 800 new houses were built, what is the percentage of houses that are not renovated?
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
Of the 3,200 houses, %283%2F4%29%2A3200+=+2400 are older than 100 years.
%281%2F3%29%2A2400+=+800 were renovated, and so 2,400 - 800 = 1,600 stayed unrenovated.
800 new houses built means that there are now 4,000 houses in total.
===> 1600%2F4000+=+2%2F5, or 40% of the houses are not renovated.