#question number 13

12 messages · Page 1 of 1 (latest)

native novaBOT
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lyric chasm
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So it took 2 hrs for 21 km and 1.5 hrs for 21 km

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Let’s call the runner speed x and the wind speed s

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So we have x - s = 21 kilometers / 2 hours

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And x + s = 21 kilometers / 1.5 hours

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x - s = 10.5 kmh

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x + s = 14 kmh

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Add both equations to cancel the s

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And solve for x

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Then plug x back in and see if you are correct

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Are u good now?