The answer: 34 mi. / gal ; or, write as : "34 miles per gallon" .
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Explanation:
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Convert "15 km / L" (that is: "kilometers per Liter") to its value, in units of
"mi / gal " (that is, "miles per gallon).
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Note the following conversions.
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1 km ("kilometer/s") = 1000 m ("meters");
1 m ("meter") = 3.2 ft ("feet" (plural)or "foot (singular)."
5280 ft. ("feet") = 1 mi. ("mile(s)") .
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1 L ("Liter"), or ("liter") = 0.264172051242 gal ("gallon/s").
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Let us solve by using a technique known as "dimensional analysis".
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(15 km / 1 L ) = _?_ mi. / gal ?? ;
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(15 km / 1 L)*(1 L / 0.264172051242 gal)*(1000m/ 1km)* (3.2 ft /1 m)*
(1 mi. / 5280 ft) = _?_ mi. / gal ??
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On the left -hand side of the equation, the units of: "km", "L", "m", "ft" ; cancel to "one' ; and we are left with:
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→ [(15 * 1000 * 3.2) / (0.264172051242 * 5280)] mi. / gal ;
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→ = [(48000) / (1394.82843055776)] mi. / gal ;
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= 34.4128345453970259 mi/ gal; round to 2 (two) significant figures ;
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→ 34 mi. / gal ; or, write as 34 miles per gallon.
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