SOLUTION: Your brother and sister took turns driving on a 580 mile trip that took 10 hours to complete. YOur brother drove at a constant speed of 55 miles per hour and your sister drove at a
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Question 406602: Your brother and sister took turns driving on a 580 mile trip that took 10 hours to complete. YOur brother drove at a constant speed of 55 miles per hour and your sister drove at a constant speed of 60 miles per hour. how long did each person drive? Answer by mananth(16946) (Show Source):
You can put this solution on YOUR website! let brother drive for x hours
sister drive for y hours
..
x+y =10
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d=time * speed
55x+60y=580
x+y=10 .............1
55x+60y =580.............2
-55
Multiply (2) by 1
-55x+-55y=-550
55x+60y =580
Add the two equations
5y=30
/5
y=6 sister's speed
distance she drove = 6*60= 360 miles
Plug value of y in
x+y=10
x+6=10
x=4 brother's speed
distance brother drove = 4*55=220 mile
