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An urn contains 4 white and 3 red balls....

An urn contains 4 white and 3 red balls. Let 'X' be the number of red balls in a random draw of three balls. Find the mean and variance of X.

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MODERN PUBLICATION-MOCK TEST-2-EXERCISE
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  4. If y=xlog[(ax)^-1+a^-1], prove that : x (x+1) (d^2y) / (dx^2) + xdy/dx...

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  6. Evaluate : int1^4 (3x^2+2x)dx as the limit of sum.

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  8. Find the particular solution of the differential equation (1+e^(2x))dy...

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  9. Using vectors, find the area of the triangle having vertices A (1, 1, ...

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  10. Find the co-ordinates of the foot of the perpendicualr drawn from the ...

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  11. There are 40 scholars in a class, out of which 10 are sports- persons....

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  12. let A = N xxN and * be the binary operation on A defined by : (a,b) * ...

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  18. Convert 5283 meters to kilometers.

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  19. An urn contains 4 white and 3 red balls. Let 'X' be the number of red ...

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  20. For three persons A, B and C the chances of being selected as Manager ...

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