SOLUTION: It takes Darline 20 minutes to drive to work in light traffic. To come home, when there is heavy traffic, it takes her 36 minutes. Her speed in light traffic is 24 miles per hour f

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Question 1122830: It takes Darline 20 minutes to drive to work in light traffic. To come home, when there is heavy traffic, it takes her 36 minutes. Her speed in light traffic is 24 miles per hour faster than her speed in heavy traffic. Find her speed in light traffic and in heavy traffic.
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
(1) +d+=+r%2A%28+20%2F60+%29+
(2) +d+=+%28+r+-+24+%29%2A%28+36%2F60+%29+
————————————————
By substitution:
+%281%2F3%29%2Ar+=+%283%2F5%29%2A%28+r+-+24+%29+
Multiply both sides by +15+
+5r+=+9%2A%28+r+-+24+%29+
+5r+=+9r+-+216+
+4r+=+216+
+r+=+54+
And
+r+-+24+=+30+
—————————
Her speed in light traffic is 54 mi/hr
Her speed in heavy traffic is 30 mi/hr
——————
Check:
(1) +d+=+54%2A%281%2F3%29+
(1) +d+=+18+ mi
And
(2) +d+=+30%2A%283%2F5%29+
(2) +d+=+18+ mi
OK