Let T1 and T2 be the event that computer is produced by plant T1 and T2 respectively. Again, let D and ND be the event that computer produced is defective and non-defective respectivelyP(T1)=10020,P(T2)=10080,P(D)=1007Again let P(D/T1)=10P(D/T2)=k∴P(D/T1)=k and P(D/T2)=kNow,P(D)=P(T1)P(D/T1)+P(T2)P(D/T2)⇒1007=10020×k+10080×10k⇒7=20k+8k⇒k=41Now, required probability =P(T2/ND)=P(T1)P(ND/T1)+P(T2)P(ND/T2)P(Tz)P(ND/T2)