https://preparationpoint.info/mathematics-mcqs/basic-maths-mcqs/a-can-lay-a-railway-track-between-two-given-stations-in-16-days-and-b-can-do-the-same-job-in-12-days-with-help-of-c-they-did-the-job-in-4-days-only-then-c-alone-can-do-the-job-in_________/