A fermentor with volume V is vigorously agitated with an impeller of diameter Di, rotating at an rpm of n. Mixing time t
In aptitude and reasoning, quantitative reasoning dictates that ratio, percentage and series logic determine correct calculation. Therefore increase in both Di and rpm and decrease in volume of the reactor is correct as it meets mathematical and logical criteria, supported by mechanistic studies and conserved across related systems.
Ref: Agrawal, Quantitative Aptitude for Competitive Examinations, Chapter 5, Logical Reasoning and Probability, covers ratios, percentages, series completion, time-distance and analytical reasoning explaining problem-solving strategies for competitive assessments.
