Temperature is the degree of the measure that estimates the cold and hot levels of the substance. The temperature outside in degrees Celsius is [tex]\rm 20.2^{\circ}\;\rm C[/tex].
According to the law when the pressure of the system is constant then the amount of the volume of the substance occupied in the system will be directly proportional to the temperature.
In the given condition the moles and pressure is constant and can be shown as,
[tex]\begin{aligned}\rm \dfrac{T_{1}}{V_{1}} &= \rm \dfrac{T_{2}}{V_{2}} \\\\\rm T_{2} &= \rm T_{1}(\dfrac{V_{2}}{V_{1}})\end{aligned}[/tex]
The volume can be written as:
[tex]\begin{aligned}\rm T_{2} &= \rm T_{1}(\dfrac{V_{2}}{V_{1}})\\\\&= \rm T_{1} (\dfrac{r_{2}^{3}}{r_{1}^{3}})\end{aligned}[/tex]
Given,
Substituting values in the above equation:
[tex]\begin{aligned} \rm T_{2} &= (19 ^{\circ}\rm C) \times ((\dfrac{51}{2})(\dfrac{50}{2}))\\\\&= 20.2 ^{\circ}\;\rm C\end{aligned}[/tex]
Therefore, the temperature outside in degrees Celsius is [tex]\rm 20.2^{\circ}\;\rm C.[/tex]
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