SOLUTION: A typist figures out that if she types 2 pages above her work quota daily, she will complete her work 3 days ahead of schedule, and if she makes 4 pages extra per day, she will fin

Let P = the number of pages to print daily according to the schedule, and let D = the number of days to print according to the schedule.

Then you have these two equations

(P+2)*(D-3) = P*D    (1)   (P*D = total number of pages) 
(P+4)*(D-5) = P*D    (2)    

We have two equations in two unknowns, but the equations are non-linear.
Simplify each of the equations. Equation (1) becomes 

PD + 2D - 3P - 6 = PD,  or,  canceling PD in both sides,
2D - 3P - 6 = 0,  or
2D - 3P = 6.         (3)


Equation (2) becomes 

PD + 4D - 5P - 20 = PD,  or,  canceling PD in both sides,
4D - 5P - 20 = 0,  or
4D - 5P = 20.        (4)


Now we have an equivalent system of two equations (3) and (4) in two unknowns, but this time the equations are linear:

2D - 3P = 6.         (3)
4D - 5P = 20.        (4)


Multiply equation (3) by 2 and then subtract from equation (4) (both sides). You will get

-5P - (-6P) = 20 -12 = 8  --->  P = 8. 

Thus the number of pages to be printed daily is 8, according to the schedule.

Then from (3) 2D = 6 + 3*P = 6 + 3*8 = 30  ====>  D = 15.


Answer. The schedule is to print 8 pages daily in 15 days.