SOLUTION: On a weekend trip you average 35 miles per hour in the city and 60 miles per hour on the highway. If the 150 mile trip took 3 hours how much of the time were you dron

Algebra ->  Test -> SOLUTION: On a weekend trip you average 35 miles per hour in the city and 60 miles per hour on the highway. If the 150 mile trip took 3 hours how much of the time were you dron      Log On


   

Question 335532: On a weekend trip you average 35 miles per hour in the city and 60 miles per hour on the highway. If the 150 mile trip took 3 hours how much of the time were you droning in the city
Found 2 solutions by Fombitz, nyc_function:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Rate*Time=Distance
.
.
.
In the city,
35%2AT1=D1
.
.
.
On the highway,
60%2AT2=D2
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.
.
D1%2BD2=150
1.35T1%2B60T2=150
.
.
2.T1%2BT2=3
From eq. 2,
T2=3-T1
Substitute into eq. 1,
35T1%2B60%283-T1%29=150
35T1%2B180-60T1=150
-25T1=-30
T1=6%2F5hr
T1=%286%2F5%29%2860%29=72 minutes

Answer by nyc_function(2741) About Me  (Show Source):
You can put this solution on YOUR website!
Let C = hours in city
Let H = hours on highway
35C + 60H = 150
C + H = 3
Let's solve this by eliminating H.
Multiply both sides of the second equation by 60:
60C + 60H = 180
Now subtract the original first equation:
(60C + 60H) - (35C + 60H) = 180 - 150
Simplify by combining like terms:
25C = 30
Divide both sides by 25:
C = 30/25 = 6/5 hours, which is 72 minutes, or 1 1/5 hours, or 1 hour and 12 minutes, which is the same thing as 72 minutes.