How to figure out composite figures

Officer brimberry wrote 24 tickets for traffic violations last week, but only 9 tickets this week. what is the percent decrease? give your answer to the nearest tenth of a percent.

The conversion factor relating feet to meters is 1 ft=0.305 m. keep in mind that when using conversion factors, you want to make sure that like units cancel leaving you with the units you need. you have been told that a certain house is 164 m2 in area. how much is this in square feet?

If f(x)=x^3 and g(x)=2x+7 when g(x)=-5