Assume

Two naughty boys broke the glass in a front door. The glass measured 105 cm × 150 cm and was 6 mm thick. They decided to pay for the glass from their savings and, assuming it would weigh no more than 12 kg, planned to carry it and ask the caretaker to install it. What is the actual weight of the glass in kilograms? (The density of glass is 2.6 g/cm³.)

Final Answer:

m =  24.57 kg

Step-by-step explanation:

$$\begin{gathered} a=105\text{cm} \\ b=150\text{cm} \\ c=6\text{mm}\to \text{cm}=6:10\text{cm}=0.6\text{cm} \\ V=a\cdot b\cdot c=105\cdot 150\cdot 0.6=9450{\text{cm}}^3 \\ \rho =2.6{\text{g/cm}}^3 \\ {m}_1=\rho \cdot V=2.6\cdot 9450=24570\text{g} \\ m=m_1\to \text{kg}=m_1:1000\text{kg}=24570:1000\text{kg}=24.57\text{kg} \\ m>12kg \end{gathered}$$

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