SOLUTION: Anita rode her bike from her home to the repair shop at an an average speed of 30 kph. She then walked home at an average speed of 6 kph. If her total traveling time was 45 minutes

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Question 1151459: Anita rode her bike from her home to the repair shop at an an average speed of 30 kph. She then walked home at an average speed of 6 kph. If her total traveling time was 45 minutes, what was the distance from her home to the repair shop?
Found 3 solutions by josgarithmetic, Edwin McCravy, Alan3354:
Answer by josgarithmetic(39630) About Me  (Show Source):
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                  SPEED           TIME         DISTANCE

GOING              30             d/30          d

RETURN              6             d/6           d

TOTAL                           3%2F4

45 minutes is three-fourths of an hour.

d%2F30%2Bd%2F6=3%2F4
-
60%28d%2F30%2Bd%2F6%29=60%283%2F4%29
2d%2B10d=45
12d=45
d=45%2F12=%283%2A15%29%2F%283%2A4%29
d=15%2F4
highlight%28d=3%263%2F4%29

Answer by Edwin McCravy(20064) About Me  (Show Source):
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Anita rode her bike from her home to the repair shop at an average speed of 30
kph. She then walked home at an average speed of 6 kph. If her total traveling
time was 45 minutes, what was the distance from her home to the repair shop?
We make a DRT-chart

         Distance |  Rate  |Time = Distance/Rate
------------------------------------------------
Riding  |         |        |       
Walking |         |        |        
------------------------------------------------
                        Total time    

We let the distance from her home to the repair shop be x, and
we fill in the given rates for riding. 


         Distance |  Rate  |Time = Distance/Rate
------------------------------------------------
Riding  |   x     |   30   |       
Walking |   x     |    6   |        
------------------------------------------------
                        Total time    

We fill in the times using Distance/rate and the
total time of 45 minutes, which we change to 3/4 hour.

         Distance |  Rate  |Time = Distance/Rate
------------------------------------------------
Riding  |   x     |   30   |       x/30
Walking |   x     |    6   |        x/6
------------------------------------------------
                       Total time   3/4

The equation comes from the right-most column:

x%2F30%2Bx%2F6=3%2F4

The LCD is 60 so multiply each term by 60 to clear the 
fractions:

2x%2B10x=45
12x=45
x=45%2F12
x=+3%263%2F4 kilometers.

Edwin

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Anita rode her bike from her home to the repair shop at an an average speed of 30 kph. She then walked home at an average speed of 6 kph. If her total traveling time was 45 minutes, what was the distance from her home to the repair shop?
==================
Avg speed of the round trip = 2*30*6/(30+6) = 10 km/hr
-----
d = r*t = 10*0.75
d = 7.5 km RT
d one way = 3.75 km