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# Unit: Exploring one-variable quantitative data: Percentiles, z-scores, and the normal distribution

AP Stats:
UNC (BI)
,
UNC‑1 (EU)
,
VAR (BI)
,
VAR‑2 (EU)
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#### 0

Possible mastery points

This unit takes our understanding of distributions to the next level. We'll measure the position of data within a distribution using percentiles and z-scores, we'll learn what happens when we transform data, we'll study how to model distributions with density curves, and we'll look at one of the most important families of distributions called Normal distributions.

AP Stats:
UNC (BI)
,
UNC‑1 (EU)
,
UNC‑1.G (LO)
,
UNC‑1.G.4 (EK)
,
UNC‑1.I (LO)
,
UNC‑1.I.5 (EK)

## Z-scores

AP Stats:
VAR (BI)
,
VAR‑2 (EU)
,
VAR‑2.B (LO)
,
VAR‑2.B.1 (EK)
,
VAR‑2.B.2 (EK)
,
VAR‑2.C (LO)
,
VAR‑2.C.1 (EK)

### Practice

#### Quiz 1

Level up on the above skills and collect up to 240 Mastery points

AP Stats:
UNC (BI)
,
UNC‑1.F (LO)
,
UNC‑1.F.2 (EK)
,
UNC‑1.M (LO)
,
UNC‑1.M.2 (EK)
,
VAR‑6.A.1 (EK)

AP Stats:
VAR (BI)
,
VAR‑2 (EU)
,
VAR‑2.A (LO)
,
VAR‑2.A.2 (EK)
,
VAR‑2.A.3 (EK)
,
VAR‑2.A.4 (EK)

## Normal distribution calculations

AP Stats:
VAR (BI)
,
VAR‑2 (EU)
,
VAR‑2.B (LO)
,
VAR‑2.B.3 (EK)
,
VAR‑2.B.4 (EK)

### Practice

#### Quiz 2

Level up on the above skills and collect up to 320 Mastery points
Up next for you:

#### Unit test

Level up on all the skills in this unit and collect up to 700 Mastery points!
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