SOLUTION: John drives to Sarah's house 120 miles away. He travels at 25 mph half of the time and 50 mph the other half. How long does it take him to arrive at Sarah's house?
Answer must be
Algebra ->
Customizable Word Problem Solvers
-> Travel
-> SOLUTION: John drives to Sarah's house 120 miles away. He travels at 25 mph half of the time and 50 mph the other half. How long does it take him to arrive at Sarah's house?
Answer must be
Log On
Question 917832: John drives to Sarah's house 120 miles away. He travels at 25 mph half of the time and 50 mph the other half. How long does it take him to arrive at Sarah's house?
Answer must be in mixed number form.
I solved it two different ways and not sure which is correct
1. 120 miles = 25mph(T)+50mph(T)
120 miles = 75mph(T)
120/75 hours = T
T = 1 3/5 hours
2. 120 miles =25mph(1/2T)+50mph(1/2T)
120 miles = 75/2(T)
240/75 hours = T
T = 3 1/5 hours
Which way is correct?
Thank you!
You can put this solution on YOUR website! They are both correct the only difference is what you solved for. In the first equation you said that t equals half the amount time traveled. In the second equation you said that t equals the entire time traveled. If you multiply two times the t in the first equation it should equal t in the second equation.
t1=half the amount of time traveled
t2=the entire time traveled
2t1=t2
t1=1+3/5
t2=3+1/5
2(1+3/5)=3.2
2+6/5=3.2
2+1.2=3.2
(