1cm = 10 mm
3 tyg.= 3 * 7 dni = 21 dni
21 * 24 h = 504 h
proporcja:
Jeżeli:
10 mm------504 h
to:
x [mm]------1 h
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504 * x = 10 * 1
504x=10
x=0,0198… mm \approx 0,02 mm
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albo:
\frac{10}{504}=\frac{x}{1}
504 * x = 10 * 1
dalej tak samo