Answer: 2.55 cm
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Work Shown
1 foot = 12 inches
12.75 ft = 12.75*12 inches = 153 inches
The scale of 1 cm : 60 in allows us to form the proportion below
(1 cm)/(60 in) = (x cm)/(153 in)
1/60 = x/153
1*153 = 60*x ..... cross multiply
153 = 60x
60x = 153
x = 153/60
x = 2.55
The length of the component in the drawing is 2.55 cm
Side note: This is equivalent to 25.5 mm since 1 cm = 10 mm (ie you multiply by 10 to go from cm to mm).