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EOC Statistics and Probability Flashcards

6 cards from real EOC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 6 EOC Statistics and Probability flashcards as text
  1. In a normal distribution, approximately what percentage of data falls within one standard deviation of the mean?

    Answer: 68%

    In a normal distribution, approximately 68% of data falls within one standard deviation of the mean, following the empirical rule (68-95-99.7 rule).

  2. What is the interquartile range (IQR)?

    Answer: The difference between the third and first quartiles (Q3 − Q1)

    The IQR is Q3 minus Q1 and represents the range of the middle 50% of data, making it resistant to the effects of outliers.

  3. Which sampling method involves dividing a population into subgroups and randomly selecting from each subgroup?

    Answer: Stratified random sampling

    Stratified random sampling divides the population into distinct subgroups (strata) and selects a random sample from each stratum to ensure representation.

  4. A coin is flipped 3 times. What is the probability of getting exactly 2 heads?

    Answer: 3/8

    There are 8 possible outcomes (HHH, HHT, HTH, THH, HTT, THT, TTH, TTT), and 3 contain exactly 2 heads, giving a probability of 3/8.

  5. What type of graph is best for displaying the frequency distribution of continuous data?

    Answer: Histogram

    A histogram uses adjacent bars to display the frequency of data within continuous intervals (bins), making it ideal for showing distributions of continuous data.

  6. What does it mean when we say a sample is 'biased'?

    Answer: The sample does not accurately represent the population

    A biased sample is one that systematically over- or under-represents certain groups in the population, leading to inaccurate conclusions about the whole.