A class consist of 30 boys and 20 girls of which half the girls have blue eyes. Find the probability that a certain student chosen at random is a boy or has blue eyes.

Explanation

Total number of boys `= 30`

Total number of girls ` = 20`

Total number of students ` = 30+20 = 50`

Total number of students having blue eyes ` = 30/2+20/2 = 25`

Total number of students who are boys and have blue eyes ` = 30/2= 15`

Probability that a student chosen is boy, `P(A) = 30/50 = 3/5`

Probability that a student chosen is blue eyed, `P(B) = 25/50 = 1/2`

Probability that a student chosen is a boy and blue eyed, `P(AnnB) = 15/50 = 3/10`

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