



 
Hi Jyoti. If the flow rates are the same, as indicated, then the ratio of the areas of the crosssection of the pipes is the same as the ratio of the times. Since the area of a circle varies as the square of the diameter, the diameter of a circle varies as the square root of the area. Thus, the ratios of the diameters must be the square root of the ratios of the filling times. Hope this helps,  


Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences. 