A company in the furniture industry purchases wood boards from two suppliers. Each supplier ships the boards in batches of boards that are checked upon receipt. This control allows to conclude that the board is either compliant or non-compliant.

The results of the inspection of two batches of pieces are presented in the table below.

Result of the quality Result of the quality Result of the quality test test test Conforming part Non-conforming Total (C) part (C') Supplier 310 20 330 Bois-Design (E1) Supplier Inter-Bois 390 80 70 (E2) Total 700 100 800