Last weekend two college students were returning to school 2

Last weekend two college students were returning to school 200 miles away. During a blizzard, they were only able to average 25 miles per hour. For the rest of their trip, they averaged 55 miles per hour. If the entire trip took 4 hours, how long were they driving in the blizzard?

Solution

D=RT
200=25T+55(4-T)
200=25T+220-55T
200-220=-30T
T=-20/-30
T=2/3 OR 40 MINUTES DRIVING IN THE BLIZZARD.
4-2/3=3 1/3 OR 10/3 HOURS DRIVING @ 55 MPH.
PROOF:
200=25*2/3+55*10/3
200=50/3+550/3
200=600/3
200=200