On a drive from your ranch to Austin, you
wish to average 48 mph. The distance from
your ranch to Austin is 78 miles. However,
at 39 miles (half way), you find you have
averaged only 36 mph.
What average speed must you maintain in
the remaining distance in order to have an
overall average speed of 48 mph? Answer in
units of mph.
I thought the answer would be 60MPH but apparently that's wrong. Do I have to factor time into this equation?