Question 478422
68/(p+5)+3/p=3
68p+3(p+5)=3p(p+5)
68p+3p+15=3p2+15p
3p2-56p+15=0
*[invoke quadratic "x", 3, -56, 15 ]
p=18.3948514793788 or 0.27181518728787
Throwing out the smaller answer, we get the speed of the boat on the second part of the trip to be 18.3948514793788 mph.  On the first part it was 23.3948514793788 mph..