Answer: 
The correct answer to this question is option (1). 
Explanation: 
 Let x1 = Is number of pages that printer A can print in page/minute. 
 thus x1 + 5 = Is number of page that printer B can print in page/minute. 
 As printer A finishes his work in 60 min. So the task has 60x1 pages. As printers A and B both finish that task in 24 minutes. So the equation can be given as: 
60x1 = 24x1 + 24(x1 + 5) 
 
60x1 = 24x1 + 24x1 + 120 
 
60x1=48x1 + 120 
 
 60x1-48x1=120 
 
 12x1=120 
 
 x1=120/12 
 
x1=10 
 put the value of x1 in to (60x1). Therefore, the task has 60(10) = 600 pages. the task contains 600 pages. 
So the answer to this question is option (1).