An audience of 450 people is seated in an auditorium. Each row contains the same number of seats and each seat in the auditorium is occupied. With three fewer seats per row, and five extra rows, the same audience could still be seated, occupying all seats. How many rows does the auditorium have?

Question

anonymous · Answer

Sorry I tried and failed... :P

anonymous · Answer

oh wow, i got it by pure luck guessing. there are originally 18 seats per row and 25 rows.
18*25=450

(18-3)(25+5)
=15*30
=450

as for the algebraic way to solve it, i'm not quite sure.

hero · Answer

To do it algebraically: 

xy = 450
(x-3)(y+5) = 450

hero · Answer

I can provide steps if you like

hero · Answer

I wonder how long it took loophole to figure it out by guessing

anonymous · Answer

second guess :P

hero · Answer

Good job either way