Question 588889
{{{D=rt}}} Start with the distance-rate-time formula.



{{{20=40*t}}} Plug in {{{D=20}}} and {{{r=40}}}.



{{{20/40=t}}} Divide both sides by 40 to isolate 't'.



{{{0.5=t}}} Divide {{{20/40}}} to get {{{0.5}}}.



{{{t=0.5}}} Rearrange the equation.



So it will take {{{0.5}}} hours (which is {{{30}}} minutes) to go {{{20}}} miles traveling at {{{40}}} mph.