1 S sold 60 copies of book during 7days, it sold different numbers of copies on any 2 of 7days, for the 7days, s sold greatest number copies on Saturday and second greatest number copies on Friday,did S sell more than 11 copies on Friday?
(1) s sold 8 copies on Friday (2) s sold 38 copies of book on Saturday
answer B
2 T prepared 4 different letters to be sent to 4 different addresses. For each letter, T prepared an envelope with correct address .If the 4 letters are to be put into 4 envelopes at random ,what is the probability ,that only 1 letter wiil be put into the envelope with its correct address?
answer 1/3
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