On an examination given to 40 students, 5% received an A, 20% a B, 40% a C, 25% a D?

On an examination given to 40 students, 5% received an A, 20% a B, 40% a C, 25% a D, and 10% an F. If a student is selected at random, the probability that the student received neither the mark D nor an F is:





(a) 0.75


(b) 0.65


(c) 0.35


(d)0.675

On an examination given to 40 students, 5% received an A, 20% a B, 40% a C, 25% a D?
1 - .25 - 0.10 = 0.65


so (b)


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Reply:answer b
Reply:Hi,


Neither D nor F means, the student gets either A, or B or C,


The probability is (5 + 20 + 40) % = 65% = 65/100 = 0.65





(b) is the right answer.