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Algebra Difficulty 2.6 Junior Find the answer

It is known that student A and student B have the same average score for jumping rope in 1 minute. If the variance of student A's 1-minute jumping rope score is SA2=0.06S_{A}^{2}=0.06, and the variance of student B's 1-minute jumping rope score is SB2=0.35S_{B}^{2}=0.35, then which of the following is true?

Pick one

Solution

Given that student A and student B have the same average score for jumping rope in 1 minute, we compare their score stability by looking at their variances. The variance measures the spread of the scores around the mean; a lower variance indicates that the scores are more tightly clustered around the mean, implying greater stability.

- The variance of student A's 1-minute jumping rope score is given as SA2=0.06S_{A}^{2}=0.06.
- The variance of student B's 1-minute jumping rope score is given as SB2=0.35S_{B}^{2}=0.35.

To determine which student's score is more stable, we compare the variances:
SA2=0.06<0.35=SB2.S_{A}^{2} = 0.06 \lt 0.35 = S_{B}^{2}.

Since a lower variance indicates greater stability, and SA2<SB2S_{A}^{2} \lt S_{B}^{2}, it follows that student A's score is more stable than student B's score.

Therefore, the correct answer is A\boxed{A}.

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.