# Ruler

How far from Peter stands 2m hight John? Petr is looking to John over ruler that keeps at arm's distant 60 cm from the eye and on the ruler John measured the height of 15 mm.

Result

x =  80 m

#### Solution:

x / 2 = 0.60 / 0.015

x = 80

x = 80

Calculated by our simple equation calculator.

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