Answer: Third quartile =$21.58
Step-by-step explanation:
Let x be value of a stock .
For uniform distribution,
probability density function = [tex]\dfrac{1}{b-a}=\dfrac{1}{25.17-10.82}=\dfrac1{14.35}=\dfrac{100}{1435}[/tex]
Let a be the stock value such that P(x<a) =75% or 0.75
[tex]\Rightarrow\ \int ^{a}_{10.82}f(x)\ dx=0.75\\\\\Rightarrow\ \int ^{a}_{10.82}\dfrac{100}{1435}\ dx=0.75\\\\\Rightarrow\dfrac{100}{1435}[x]^{a}_{10.82}=0.75\\\\\Rightarrow \dfrac{100}{1435}(a-10.82)=0.75\\\\\Rightarrow a-10.82=0.75\times\dfrac{1435}{100}\\\\\Rightarrow a-10.82=10.7625\\\\\Rightarrow a= 10.7625+10.82= $21.5825\approx $21.58[/tex]
Hence, 75% of all days the stock is below $21.58 or Third quartile =$21.58 .
