Question

Dylan is trying to plot a histogram on his personal computer with 105 data points. If he decides to group 15 data points at a time, the number of rectangular bars he creates is .

Answer 1

When data is in grouped format, the range intervals are plotted on the horizontal axis. The vertical axis represents the frequency corresponding to each interval range to form a histogram.

Here, each rectangle corresponds to each range interval of the data set.

Total number of data points $=105$
Number of data points in each interval $=15$
$\therefore$ Number of intervals $=\frac{\text{Total number of data points}}{\text{Number of data points in each interval}}$
$=\frac{105}{15}$
$=7$

$\therefore$ He will have $7$ intervals and hence $7$ rectangular bars.

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