Aplane takes off from new york with 72 of the 90 seats occupied what is what percentage of seats are not occupied?

20%

Because since there are 72 seats taken, that means there are 18 seats that are not occupied (90-72).

Then you can divide 18 by 90 to get 0.2. Multiple 0.2 by 100 to get percent. 

Then you get 20%

What are the following algebraic equations. you need to post those if you want the answer