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Refer to Table 14.7, Chapter 14 (i) Find...

Refer to Table 14.7, Chapter 14
(i) Find the probability that a student obtained less than 20% in the mathematics test.
(ii) Find the probability that a student obtained marks 60 or above.

Text Solution

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Here, the total number of students, `N = 90`
Number of students those who obtained less than `20%` marks `E_l= 7`
Number of students those who obtained `60 or above` marks `E_g= 15+8 = 23`
(i)Probability a student obtained less than `20%` marks, `P(E_l) = E_l/N = 7/90`
(ii)Probability a student obtained `60 or above` marks, `P(E_g) = E_g/N = 23/90`
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