The meanings of the prefixes kilo- and hecto- are ...
1 kg = 1000 g
1 hg = 100 g
So, 1 kg = 1000 g = 10×100 g = 10 hg.
Your conversion is ...
6 kg = (6 kg)(10 hg/kg) = 60 hg
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For any units conversion, multiply by a ratio whose value is 1. The numerator of the ratio should contain the units you want, and the denominator should contain the units you want to cancel.
