Answer: [tex]x=\dfrac{3240}{83}[/tex]
Step-by-step explanation:
Given: 83 : 45 :: 72 : ?
Let unknown quantity (?) be x.
Now, x : y :: a : b
[tex]\Rightarrow\ \dfrac{x}{y}=\dfrac{a}{b}[/tex]
83 : 45 :: 72 : x
[tex]\Rightarrow\ \dfrac{83}{45}=\dfrac{72}{x}\\\\\Rightarrow\ x=\dfrac{72}{83}\times45\\\\\Rightarrow\ x=\dfrac{3240}{83}[/tex]
Hence, [tex]x=\dfrac{3240}{83}[/tex]