- CFA Exams
- CFA Level I Exam
- Study Session 2. Quantitative Methods (1)
- Reading 7. Statistical Concepts and Market Returns
- Subject 6. Measures of Dispersion

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**CFA Practice Question**

If you are told a population has a mean of 25 and a variance of 0, what must you conclude?

A. Someone has made a mistake.

B. There is only one element in the population.

C. All the elements in the population are 25.

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**User Contributed Comments**
5

User |
Comment |
---|---|

Daddykay |
eg consider a pop with elements: 25,25,25 Mean=75/3=25 Var=0 |

bashg |
Can it also be that there is only one element in the population. That element being 25 Mean 25/1 =25 var = 0 |

rana1970 |
But option B never say that one element is 25 |

JonClark |
Yes, B can be correct... But it's not the only possible population. The question asks, "what must you conclude?" |

Shaan23 |
Thats not easy...it is but not at the same time... |