Chocolate - comparing

Robert has 8.2 cm, 3.1 cm, and 0.8 cm long chocolate. Norbert has 0.4 cm, 5 cm and 7.9 cm chocolate. Which one has more chocolate, and how much?

Correct answer:

x = R
v =  4.536 cm³

Step-by-step explanation:

$$\begin{gathered} a=8.2\text{cm} \\ b=3.1\text{cm} \\ c=0.8\text{cm} \\ A=0.4\text{cm} \\ B=5\text{cm} \\ C=7.9\text{cm} \\ {V}_1=a\cdot b\cdot c=8.2\cdot 3.1\cdot 0.8=\frac{2542}{125}=20\frac{42}{125}=20.336{\text{cm}}^3 \\ {V}_2=A\cdot B\cdot C=0.4\cdot 5\cdot 7.9=\frac{79}{5}=15\frac{4}{5}=15.8{\text{cm}}^3 \\ {V}_1>V_2 \\ x=R \end{gathered}$$

$v=V_1-V_2=20.336-15.8=4.536{\text{cm}}^3$

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