0.4724409449 in. Direct Conversion Formula. 12. mm. * 1 in. 25.4. mm. = 0.4724409449 in.
http://wiki.answers.com/Q/What_does_12_MM_equal_in...

In an inch there are 2.54 centimeters. Converting inches to centimeters is accomplished by simply multiplying the number of inches by 2.54.
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12 mm*10 cm/1 mm=120 cm then 120 cm* 1 inch/2.54 cm=47.24409 inch therefore 12mm is equal to 47.24 inches
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