Daniel drives 30 mph to the toy store and 45 mph back home, taking the same route both ways. If the total trip took two hours, how many total miles does he drive on the round-trip from home to the store and back?
Can you please explain how to do it?
3 answers
How long did he spend at the toy store?
It doesn't say
let the distance each way be x miles
time for first trip = x/30
time for return trip = x/45
x/30 + x/45 = 2
multiply by 90 , the LCD
3x + 2x = 180
5x = 180
x = 36
So the roundtrip was 72 miles
check:
time at first leg of trip = 36/30 = 1.2 hrs
time at 2nd leg of trip = 36/45 = .8 hrs
total time = 1.2+.8 hrs = 2 hrs
time for first trip = x/30
time for return trip = x/45
x/30 + x/45 = 2
multiply by 90 , the LCD
3x + 2x = 180
5x = 180
x = 36
So the roundtrip was 72 miles
check:
time at first leg of trip = 36/30 = 1.2 hrs
time at 2nd leg of trip = 36/45 = .8 hrs
total time = 1.2+.8 hrs = 2 hrs