Grouped Data and Histograms (HSC SSCE Mathematics Advanced): Quizzes

To reduce complexity and show patterns

The midpoint of an interval

$80 \leq \text{value} < 90$

They join with no gaps between them

On the horizontal axis at both ends

At zero at the bottom left corner

$\bar{x} = \frac{\sum xf}{n}$

$s^2 = \frac{\sum x^2f}{n} - \bar{x}^2$

$s = \sqrt{s^2}$

Loss of precision in calculations