document.write( "Question 923757: A car and a truck start at the same point and travel in opposite directions. The car travels 8 mi per hour faster than the truck. After 3 hours the car and the truck are 354 mi apart. Find the average speed of the car and truck.\r
\n" ); document.write( "\n" ); document.write( "I did 3(x+8)=354. X+y=118
\n" ); document.write( " 3y=354. y=118
\n" ); document.write( "But it makes no sense. Im trying to do it like ive been doing the upstream down stream but cant figure it out. Please help! Thank you! \n" ); document.write( "

Algebra.Com's Answer #560315 by MathTherapy(10552) $\"\"$ $\"About$

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\n" ); document.write( "A car and a truck start at the same point and travel in opposite directions. The car travels 8 mi per hour faster than the truck. After 3 hours the car and the truck are 354 mi apart. Find the average speed of the car and truck.\r
\n" ); document.write( "\n" ); document.write( "I did 3(x+8)=354. X+y=118
\n" ); document.write( " 3y=354. y=118
\n" ); document.write( "But it makes no sense. Im trying to do it like ive been doing the upstream down stream but cant figure it out. Please help! Thank you!
\n" ); document.write( "


\n" );
document.write( "Let truck's speed be S
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document.write( "Then car's speed = S + 8
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document.write( "In 3 hours, truck has covered: (3S) miles
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document.write( "In 3 hours, car has traveled:  3(S + 8), or (3S + 24) miles
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document.write( "In 3 hours, both vehicles have traveled a total of 354 miles
\n" );
document.write( "Therefore, it can be said that: 3S + 3S + 24 = 354
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document.write( "Solve of S, the speed of the truck
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document.write( "Add 8 to truck's speed to get car's speed\r
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document.write( "\n" );
document.write( "You should get:
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document.write( "Truck's speed:  mph
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document.write( "Car's speed:    mph \n" );
document.write( "

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