Question 176040
You must add the rates to get the combined rate
In words:
{1 water tank/time to fill with large hose) + (1 water tank/time to fill with small hose) = (1 water tank)/(time to fill with both hoses)
{{{1/4 + 1/6 = 1/x}}}
multiply both sides by {{{24x}}}
{{{6x + 4x = 24}}}
{{{10x = 24}}}
{{{x = 2.4}}}
It takes 2.4 minutes to fill the tank with both hoses