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If the mean and variance of one set of v...

If the mean and variance of one set of values be `barx_1` and `s_1^2` and those of another set be `barx_2` and `s_2^2` respectively and each set has values 2, then prove that the variance `(s^2)` of the combined set of values is given by `4s^2 = 2(s_1^2 + s_2^2) + d^2` where `d = (barx_1 - barx_2)`.

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UNITED BOOK HOUSE-Scottish Church Collegiate School, Question Paper -Exercise
  1. Suppose a variable assumes the values, 0, 1, 2,………….n with frequencies...

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  2. For any frequecy distribution

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  3. If the mean and variance of one set of values be barx1 and s1^2 and th...

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  4. Define imbibition State its significance.

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  5. The elements A, B and C have atomic numbers Z -2, Z and Z +1 respecive...

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  6. State and prove the theorem of compound probability.

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  7. The H.M of a set of values is 2. If each value is tripled, the new H.M...

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  8. If the relation between two variable x and y is 5y+7x=11 and the range...

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  9. A dinner party is to be fixed for a group of 100 persons. In this part...

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  10. If var (x) = 7, then var (5 - 3x) is equal to

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  11. The first moment about the value 4 of a variable is 3, then its mean ...

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  12. The sum of the roots of the equation x^3 + 5x + 1 = 0 is

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  13. If x is real, the minimum value of x^2 - 10x + 28 is

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  14. The two digited fermat number is

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  15. A and B are two independent events such that P(A^C) = 0.7, P(B) = k an...

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  16. For two events A and B P(A^C|B^C)+P(A|B^C)=?

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  17. Write a short note on ‘measures of dispersion’.

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  18. Describe cross sectional data with their utility.

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  19. Define Pilot survey.

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  20. If a value of a variable is zero, then what will be its geometric mean...

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