Vẽ hai góc xAy và yAz kề bù . Trên nửa mặt phẳng bờ xz không chứa tia Ay, vẽ tia At sao cho xAy = zAt a, chứng minh:tia At và tia Ay đối nhau

Peter applied to an accounting firm and a consulting firm. he knows that 30% of similarly qualified applicants receive job offers from the accounting firm, while only 20% of similarly qualified applicants receive job offers from the consulting firm. assume that receiving an offer from one firm is independent of receiving an offer from the other. what is the probability that both firms offer peter a job?