6m = 600cm
25cm - - - - - - - - - --- 1s
600 cm ------------------x s
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Avem proporționalitate directă :
[tex]\it \dfrac{25}{600} =\dfrac{1}{x} \Rightarrow x = \dfrac{600\cdot1}{25} =\dfrac{600}{25} =\dfrac{6\cdot100}{25} =6\cdot4 = 24 s[/tex]