Answers

2015-08-24T17:47:29+08:00
1millimeter is equal to 0.1 Centimeter,
so 1800mm x 0.1cm = 180cm.
So, 1800mm is equal to 180cm. 

BUT we seriously cannot see 1800millimeter in a ruler, that's because ruler has only 12inches, equal to 30.48 centimeters, very far from 180centimeters. BUT 1800mm can be found on longer measurement tools. 
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