If the subway travels and average speed of 45mph and it allows you to get to work at 8:30, when you leave your house at 7:45. One day the subway was having problems and could go 35mph. how early would you have to leave your house to make it to work on time?

Answer 1

at the regular speed it took 45 min or 3/4 hour
so the distance is 45*3/4 mi or 135/4 miles

at a speed of 35 mph it would take
135/4 ÷ 35 hours or .96429 hours
which would be 57.9 minutes

so just back up that time from his work start of 8:30

BTW, how would he have known that the subway was going to have a problem, and left earlier to still make it on time ??????