document.write( "Question 630854: Two sisters leave their house at the same time, and walk in opposite directions. In 5 hours they are exactly 20 miles apart. Find their speeds given that the older sister travels three times faster than the younger? \n" ); document.write( "
Algebra.Com's Answer #397309 by 303795(602)\"\" \"About 
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Let the younger sister's speed be x. The older sister travels at three times the speed ie at 3x.
\n" ); document.write( "In 5 hours the younger sister travels 5x miles and the older sister travels 5 times 3x = 15x miles.
\n" ); document.write( "the total distance travelled by the two girls is 5x + 15 x = 20x
\n" ); document.write( "ie 20x = 20 so x = 1
\n" ); document.write( "The younger sister is travelling at 1 mile per hour and the older sister travels at 3 miles per hour.
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