Descriptive Statistics Flashcards
7 cards from real FAST practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Descriptive Statistics flashcards as text
A dataset's mean is 50 and standard deviation is 10. A value of 70 has a z-score of:
Answer: 2
Z = (value − mean) / SD = (70 − 50) / 10 = 20 / 10 = 2.
The heights (cm) of 5 students are: 160, 165, 170, 175, 180. What is the mean absolute deviation (MAD)?
Answer: 6
Mean = 170; absolute deviations: 10, 5, 0, 5, 10; MAD = 30/5 = 6.
In a dataset, the 90th percentile value means:
Answer: 90% of values fall at or below it
The nth percentile is the value below which n% of the data falls.
Which of the following best describes a leptokurtic distribution compared to a normal distribution?
Answer: Taller peak with heavier tails
Leptokurtic distributions have positive excess kurtosis, meaning a sharper peak and heavier tails than a normal distribution.
Data: 3, 7, 7, 2, 9, 3, 7. What is the mode?
Answer: 7
7 appears three times, which is more than any other value, making it the mode.
A researcher reports a coefficient of variation (CV) of 5% for Dataset A and 40% for Dataset B. This means:
Answer: Dataset A is more consistent relative to its mean
CV = (SD/mean) × 100%; a lower CV indicates less relative variability, so Dataset A (5%) is more consistent.
When constructing a stem-and-leaf plot for the values 23, 27, 31, 35, 38, the stems would be:
Answer: 2, 3
For two-digit numbers in the 20s and 30s, the tens digits (2 and 3) serve as stems.