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Paralelipiped dreptunghic cu L= 70 cm, l = 18 cm si h = 30 cm

Se introduce apa pana la 2 treimi inaltime: h₁ = 30×2/3 = 20 cm

a) Cantitatea de apa din vas este:

[tex]\mathcal{V} = L \cdot \ell \cdot h_{1} = 70 \cdot 18 \cdot 20 = 25200 \ cm^{3} = 25,2 \ dm^{3} = 25,2 \ \ell\\[/tex]

unde: 1 dm³ = 1000 cm³ si 1 dm³ = 1 [tex]\ell[/tex]

b) Volumul total al celor 210 bile este de:

[tex]\mathcal{V}_{bile} = 210 \cdot 5 = 1050 \ cm^{3}[/tex]

[tex]\mathcal{V}_{total} = \mathcal{V} + \mathcal{V}_{bile} = 25200 + 1050 = 26250 \ cm{3}\\[/tex]

Inaltimea la care se ridica apa in vas dupa scufundarea celor 210 bile o aflam impartind noul volum la aria bazei:

[tex]h_{2} = \dfrac{\mathcal{V}_{total}}{\mathcal{A}_{baza}} = \dfrac{26250}{70 \cdot 18} = \dfrac{26250}{1260} = \dfrac{125}{6} = 20\dfrac{5}{6} \ cm\\[/tex]