Question 457718
AT the beginning of a walk, Roberto and Juanita are 9.9 miles apart.
 If they leave at the same time and walk in the same direction, Roberto overtakes Juanita in 11 hours.
 If they walk towards each other, they meet in 1 hour. What are their speeds?
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Let r = R's speed
let j = J's speed
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When they walk toward each other, their speeds are additive
When they walk the same way, the slower speed is subtracted from the faster speed
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Write a distance equation for each scenario
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11(r - j) = 9.9
simplify, divide each side by 11
r - j = .9
and
1(r + j) = 9.9
add the first simplified equation
r + j = 9.9
r - j = .9
---------------adding eliminates j, find r
2r = 10.8
r = {{{10.8/2}}}
r = 5.4 mph is R's speed
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Find j using r + j = 9.9
5.4 + j = 9.9
j = 9.9 - 5.4
j = 4.5 mph is J's speed
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