Question 331202
let the original speed be x mph
on her return it was x+11 mph
..
distance is constant = 330 miles.
..
return was 1 hour less.
time taken while going - time returning = 1 hour
..
time while going = 330/x
time while returning = 330/x+11
..
330/x-330/(x+11)=1
LCD = x(x+11)
330(x+11)-330x/  x (x+11)=1
330x+3630-330x=x(x+11)
3630= x^2 +11x
x^2+11x-3630=0
x^2+66x-55x-3630=0
x(x+66)-55(x+66)=0
(x-55)(x+66)=0
x=55 ignore negative value 

original speed = 55 mph