https://preparationpoint.info/mathematics-mcqs/basic-maths-mcqs/p-takes-twice-as-much-time-as-q-or-thrice-as-much-time-as-r-to-finish-a-piece-of-work-they-can-finish-the-work-in-2-days-if-work-together-how-much-time-will-q-take-to-do-the-work-alone-2/