Thomas has constant speeds for both running and walking. When a down-escalator is moving, Thomas can run down it in 15 seconds or walk down it in 30 seconds. One day, when the escalator was broken (and stationary), it took Thomas 20 seconds to run down it.
How long, in seconds, would it take Thomas to walk down the broken escalator?
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30
40
45
50
60
Select an option, then submit.
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