We know that Rt=R0(1+αt) where Rt is the resistance of the wire at t∘C, R0 is the resistance of the wire at 0∘C and α is the temperature coefficient of resistance ⇒R50=R0(1+50α) ......(i) R100=R0(1+100α) ......(ii) From (i),R50−R0=50αR0......(iii) From (ii),R100−R0=100αR0......(iv) Dividing (iii) by (iv), we get