Q7 of 24 Page 97

In the sample of 50 people, 21 has type “O” blood, 22 has type “A” blood, 5 has type “B” blood and 2 has type “AB” blood. If a person is selected at random find the probability that

(i) the person has type “O” blood (ii) the person does not have type “B” blood


(iii) the person has type “A” blood (iv) the person does not have type “AB” blood.

Sample Space consists of 50 different people where 1 person can only have 1 blood group.

∵ number of people with “O” blood is 21


∴ ---- (1)


Similarly,


Probability of getting Blood “B”, “A”, “AB” respectively is


---- (2)


---- (3)


---- (4)


By (1)


(i) Probability that random person among those people has “O” group = (by (1))


(ii) Probability that random person among those people does not has “B” group = (by (2))


(iii) Probability that random person among those people has “A” group = (by (3))


(iv) Probability that random person among those people does not has “B” group = (by (4))


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