Let's assume
the number of hours Susan jogs at the increased speed is 't' hours
Since, increased speed is 6 miles per hour
after 't' hours , she travles with increased speed is 6*t miles
She starts off with a half-hour walk at a pace of 2 miles per hour
so, she travels distance
=0.5*2 miles
=1 miles
She travels a total of 4 miles
total distance is
=6t+1
now, we can set them equal
now, we can solve for t
Subtract both sides by 1
Divide both sides by 6
we get
so, the number of hours Susan jogs at the increased speed is 0.5 hrs.........Answer