How high is the table?

[Math Tutor]

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[shyamjayakannan]

Let [tex]b\to[/tex] bird, [tex]d\to[/tex] dog and [tex]t\to[/tex] table. So, [tex]t+b-d=130[/tex] and [tex]t+d-b=170[/tex]. Add both to get [tex]2t=300\Rightarrow\boxed{t=150}[/tex]