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The probability distribution of a random variable x is given below.

x0123
P(x)k/3k/2k/4k/7

Then the value of k is

Solution

✅ Correct Option: 2

For any probability distribution, all probabilities must add up to 1.

P(0)+P(1)+P(2)+P(3)=1P(0) + P(1) + P(2) + P(3) = 1

k3+k2+k4+k7=1\frac{k}{3} + \frac{k}{2} + \frac{k}{4} + \frac{k}{7} = 1


To add these fractions, find the LCM of the denominators 3, 2, 4, and 7.

LCM of 3, 2, 4, 7 = 84


Convert each fraction to have denominator 84:

k3=28k84\frac{k}{3} = \frac{28k}{84}

k2=42k84\frac{k}{2} = \frac{42k}{84}

k4=21k84\frac{k}{4} = \frac{21k}{84}

k7=12k84\frac{k}{7} = \frac{12k}{84}


28k+42k+21k+12k84=1\frac{28k + 42k + 21k + 12k}{84} = 1

103k84=1\frac{103k}{84} = 1

103k=84103k = 84

k=84103k = \frac{84}{103}


Therefore, the value of kk is 84103\frac{84}{103}.

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