How can I convert m/s to mi/h using only simple unit ratios?

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To convert meters per second (m/s) to miles per hour (mi/h) using simple unit ratios, one must create a series of ratios that allow for the cancellation of units. The process involves writing ratios that include miles in the denominator and meters in the numerator to achieve the desired conversion. The discussion emphasizes that this method is essentially an exercise in simplifying unit fractions. The correct approach requires careful selection of unit ratios to ensure proper cancellation of units. Ultimately, understanding and applying these unit ratios facilitates the conversion without relying on external conversion tables.
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Ok, i know how to convert to and from the metric system and how to convert within, but what exactly am i supposed to do with this. Notice I am not asking for it solved, but guidance on how to solve, bc this seems like a really stupid way for us to have to convert with extra steps added and mixed in. Also there is not much to work out by hand i believe other than writing and cancelling out. thank you. also i believe number seven is A
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Suppose you were stranded on a desert island and didn't have a table of conversion factors, and suppose also that you'd had a coconut fall from a tree and lost your memory of all but the most basic conversion factors. Using your remaining knowledge of simple unit ratios (12 inches / 1 ft, for example), you could write one of the expressions in #7 to convert m/s to mi/h.

To start with mi/h and end with m/s, one must write a series of simple unit ratios, one of which has mi in the denominator (so as to 'cancel' mi from the final expression) and another of which that has m in the numerator (so we end up with m/s). The only answer to #7 that could be correct (can't see all of it) is answer e; its the only one that has a unit ratio with m in the numerator of one of the factors.

This is just an exercise in writing and simplifying unit ratios, aka unit fractions.
 
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