Answer :

1 centimeter = 0.1 decimeter. So 27 centimeters = 2.7 decimeters
An easy way to figure out what conversion you are doing is with..
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KHDUDCM
The UDC stands for Unit, deci, and then centi. You always have the larger number on the left hand side of the scale and the larger number gets to be 1.
27 centimeters×(1 deci/ 10 centi)= 2.7 decimenters