Probability — Class 12 Maths Solution

exemplar sa SA NCERT,Exemp,Q.15,Page.273

Question

Suppose 10000 tickets are sold in a lottery each for Rs.1. First prize is of Rs.3000 and the second prize is of Rs.2000. There are three third prizes of Rs.500 each. If you buy one ticket, then what is your expectation?

Step-by-step Solution

Let X is the random variable for the prize.

$figure$

Since, $E(X) = \Sigma XP(X)$

$\therefore$ $E(X) = 0 \times \frac{{9995}}{{10000}} + \frac{{1500}}{{10000}} + \frac{{2000}}{{10000}} + \frac{{3000}}{{10000}}$

$= \frac{{1500 + 2000 + 3000}}{{10000}}$

$= \frac{{6500}}{{10000}} = \frac{{13}}{{20}} = {\rm{Rs}}.0.65$

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NCERT & Exemplar solution for CBSE Class 12 Mathematics, Probability. Curated by Sachin Sharma. Free for all students.