I US Gallon = 3.7854118 liters
So 21 miles per gallon = 21 per 3.7854118 liters
1 mile = 1.609344 kilometers
So, 21 miles = 33.796224 kilometers
33.796224 kilometers per 3.7854118 liters = 8.928017818299187 kilometers per liter
.... call it 8.93
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1 Imperial Gallon = 4.54609 liters
So, 21 miles per gallon = 21 miles per 4.54609 liters
21 miles = 33.796224 kilometers
So 1 mile = 1.609344 kilometers
So, 33.796224 kilometers per 4.54609 = 7.43413008862759 kilometers per liter
.... call it 7.43
22 (kilometers per liter) = 51.75 miles per gallon.
9.6 (kilometers per liter) = 22.56 miles per gallon.
10 (kilometers per liter) = 23.52 miles per gallon.
45 miles per gallon = 19.13 kilometers per liter.
30 miles per gallon = 12.75 kilometers per liter.
25 miles per gallon is 10.6285927 kilometers per liter
20 miles per gallon = just over 8.5 kilometers per liter.
21 miles per gallon is 8.928 kilometers per liter.
15 (kilometers per liter) = about 35.3 miles per gallon.
8.3 kilometers per liter is about 19.5 miles per gallon.
15 km per l is 35.2821875 mpg.
10.5km/L is 24.7 miles per gallon.