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Tamil Nadu Board of Secondary EducationHSC Science Class 12

Two balls are chosen randomly from an urn containing 6 red and 8 black balls. Suppose that we win ₹ 15 for each red ball selected and we lose ₹ 10 for each black ball selected. X denotes the - Mathematics

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Question

Two balls are chosen randomly from an urn containing 6 red and 8 black balls. Suppose that we win ₹ 15 for each red ball selected and we lose ₹ 10 for each black ball selected. X denotes the winning amount, then find the values of X and number of points in its inverse images

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Sum
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Solution

Number of red balls = 6

Number of black balls = 8

‘X’ is the random variable denotes the winning amount.

∴ The values of ‘X’ are 0, 15, 30

i.e., X(BB) = 0

X(RB) = 15 + 0 = 15

X(RR) = 15 + 15 = 30

Value of X 0 15 30 Total
Number of elements in inverse images 1 2 1 4
  BB RB, BR RR  
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Chapter 11: Probability Distributions - Exercise 11.1 [Page 184]

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Samacheer Kalvi Mathematics - Volume 1 and 2 [English] Class 12 TN Board
Chapter 11 Probability Distributions
Exercise 11.1 | Q 4 | Page 184

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