Let the speeds of two ships be ' x ' and ' x+6 ' km per hour Distance covered in 2 hours will be 2x and 2x+12
It is given, (2x)2+(2x+12)2=602 (x)2+(x+6)2=302 2x2+12x+36=900 x2+6x+18=450 x2+6x−432=0 Solving, we get x=18 The speed of slower ship is 18kmph The answer is option C.