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Question: Answered & Verified by Expert
If the mean of two samples of sizes 20 and 30 are 25 and 10 respectively, their variances are 9 and 16 respectively, their combined variance is
MathematicsStatisticsAP EAMCETAP EAMCET 2020 (07 Oct Special)
Options:
  • A $67.9$
  • B $68.2$
  • C $68.1$
  • D $67.2$
Solution:
1009 Upvotes Verified Answer
The correct answer is: $67.2$
No solution. Refer to answer key.

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