SOLUTION: to mow a lawn 10 m by 10 m takes 1 hour, how long will it take to mow a lawn 20 m by 12 m?

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Question 939695: to mow a lawn 10 m by 10 m takes 1 hour, how long will it take to mow a lawn 20 m by 12 m?
Found 3 solutions by josmiceli, stanbon, MathLover1:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+10%2A10+=+100+
+20%2A12+=+240+
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Time to mow the lawns will be
proportional to their areas
+100+%2F+1+=+240%2Ft+
+100t+=+240+
+t+=+2.4+
+.4%2A60+=+24+
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It will take 2 hrs 24 min

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
to mow a lawn 10 m by 10 m takes 1 hour, how long will it take to mow a lawn 20 m by 12 m?
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time/area = time/area
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t/(20*12) = 1/(10*10)
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t = 240/100
time = 2.4 hrs = 2hr 24min
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Cheers,
Stan H.
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Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

to mow a lawn 10m by 10m takes 1h,=> a lawn 10m%2A10m=100m%5E2 takes 1h
to mow a lawn 20m+%2A12m=240m%5E2 takes t%2Ah (t hours)
time will be proportional to area
100m%5E2%3A1h=240m%5E2%3At%2Ah...solve for t
100m%5E2%2At%2Ah=240m%5E2%2Ah
100%2At=240
t=240%2F100
t=2.4h ....0.4h=0.4%2A60min=24min
t=2h and 24min is an answer to the question how long will it take to mow a lawn 20m by 12m