Answers:
b) 92100 decimeters
c) 6650 decaliters
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Work Shown for part b)
1 decameter = 10 meters
1 decimeter = 1/10 of a meter
10 decimeters = 1 meter .... multiply both sides by 10
100 decimeters = 10 meters ... multiply both sides by 10
100 decimeter = 1 decameter
921*(100 decimeter) = 921*(1 decameter)
92100 decimeters = 921 decameters
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Work Shown for part c)
We could follow the same idea as part b). I'm going to use another approach as shown in the diagram below. This conversion method is known as the railroad tracks method in some math textbooks.
Each column represents two things that are equivalent to one another. For example, 1 kiloliter is the same as 1000 liters. So each column, when you divide top over bottom, represents the value 1.
Notice the unit cancelations as shown by the color coding. The goal is to have every unit cancel except for the decaliters unit which is what we want to end up with ultimately.
Once you have the railroad tracks set up, you multiply straight across.
Along the top, we have 66.5*1000*1 = 66500
Along the bottom we have 1*10 = 10
Divide those results: 66500/10 = 6650
So 66.5 kiloliters converts to 6650 decaliters