Q90. Three balls are drawn at random from a bag containing 5 blue and 4 yellow balls. Let the random variables $X$ and $Y$ respectively denote the number of blue and yellow balls. If $\bar { X }$ and $\bar { Y }$ are the means of $X$ and $Y$ respectively, then $7 \bar { X } + 4 \bar { Y }$ is equal to $\_\_\_\_$
Q90. Three balls are drawn at random from a bag containing 5 blue and 4 yellow balls. Let the random variables $X$ and $Y$ respectively denote the number of blue and yellow balls. If $\bar { X }$ and $\bar { Y }$ are the means of $X$ and $Y$ respectively, then $7 \bar { X } + 4 \bar { Y }$ is equal to $\_\_\_\_$
\section*{ANSWER KEYS}
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1. (2) & 2. (2) & 3. (3) & 4. (1) \\
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9. (2) & 10. (2) & 11. (1) & 12. (1) \\
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17. (4) & 18. (2) & 19. (2) & 20. (1) \\
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25. (12) & 26. (748) & 27. (4) & 28. (3) \\
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33. (2) & 34. (1) & 35. (1) & 36. (4) \\
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