The maximum diameter of the hole that can be punched from a plate of maximum shear stress $${\frac{1}{4}^{{\text{th}}}}$$ of its maximum crushing stress of punch, is equal to (where t = Thickness of the plate)

Answer is wrong it Should be 1 because shear stress developed in the plate material due to any external load let's say it be p then it would be p/area of plate material on load(L*t=2πr*t=πd*t)& crushing stress developed on the punch material due to same load=p/area of punch material under stress (π/4d^2)now solve it as per the question you will get the final answer as d=t

A.1t, since (Tau*pi*d*t) = (sigma*pi*(d^2)/4), and (sigma= 4*tau)

Answer is wrong it should be 1