answer : There are 8 people staying over night
let, x = no. of people staying
y = the bill each of them are paying
xy = 4800 ...(i)
(x+4)(y-200) = 4800 = xy
xy-200x+4y-800 =xy
-200x+4y-800 = 0
taking -4 outside
⇒50x -y +200 = 0 ...(ii)
Solve (i) and (ii)
x=8
y=600
like if satisfied