What is is advantage to using equations

Well, you can put various math problems into one. Equations can also show more information easier than writing many problems. Hope this helps, and keep learning!

I am not 100% sure what you are asking here...

However, an advantage to equations is that we can find out nearly all problems. Math, Geometry, Algebra, Science, even Economics all use math in order to solve problems that they want to figure out. It would be very hard to figure out many things about the world without equations. 

Num of plants = (original#ofplants)*(1.6)^t

The answer is 225 miles per 4.5 hours. hope this ; )