IPMAT Rohtak 2019 (QA) PYQs

If the time taken by boat to travel upstream on Wednesday is $\frac{6}{7}$ times the time taken to travel downstream on Monday and the speed of boat in still water on Monday is 15 kmph, then find the speed of boat in still water on Wednesday? (Speed of boat in still water is different for different days)

If the time taken by boat to travel upstream on Monday is $27 \frac{1}{5}$ hrs more than the time taken by it to travel downstream on the same day, then find the speed of boat in still water on Monday? (speed of boat in still water is the same in upstream as in downstream)

If the speed of boat in still water on Saturday was 27 km/hr and the speed of boat in still water on Wednesday was $66 \frac{2}{3}\%$ more than that of Saturday and time taken to travel upstream on Wednesday is $\frac{16}{13}$ times than time taken by it to travel downstream on Saturday, then find the speed of stream (in kmph) on Saturday?