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NBT Statistics and Probability Flashcards

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

Read the first 7 NBT Statistics and Probability flashcards as text

  1. A scatter plot shows a strong negative correlation. Which statement best describes this relationship?

    Answer: As x increases, y decreases

    A negative correlation means that as one variable increases, the other decreases.

  2. In a normal distribution, approximately what percentage of data falls within one standard deviation of the mean?

    Answer: 68%

    The empirical rule states that approximately 68% of data falls within one standard deviation of the mean.

  3. A bag has 6 red and 4 blue chips. Two chips are drawn without replacement. What is the probability both are red?

    Answer: 1/3

    P(both red) = (6/10) × (5/9) = 30/90 = 1/3.

  4. Which of the following correctly describes a frequency histogram?

    Answer: A bar graph where bars represent frequency of data intervals

    A frequency histogram uses bars whose heights represent how often data values fall within each interval.

  5. The variance of a dataset measures:

    Answer: The average squared deviation from the mean

    Variance is the mean of the squared differences between each data point and the overall mean.

  6. If P(A) = 0.4 and P(B) = 0.5 and A and B are independent events, what is P(A and B)?

    Answer: 0.2

    For independent events, P(A and B) = P(A) × P(B) = 0.4 × 0.5 = 0.2.

  7. A stem-and-leaf plot shows: 1|3 5 7, 2|1 4 6 9. What is the median of this dataset?

    Answer: 21

    The 7 ordered values are 13,15,17,21,24,26,29; the median is the 4th value = 21.