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Here are some tips for Stem And Leaf Plots, which aligns with Minnesota state standards:

Stem and Leaf Plots


To do well in this topic, you need to know mean, median and range.
To review the basics of mean, median and range, see here.

A stem and leaf plot is a type of graph that organizes data. The stem is the left-hand column which has the tens digits. The leaves are in the right-hand column which has the ones digits.

stem leaf
2   0 3
3  
4   5 5 9
The values represented in this stem-and-leaf plot are 20, 23, 45, 45, and 49.


Example:

Calculate the mean of the data represented by the following stem and leaf plots.
Data Values
StemLeaf
03, 8
22
32
58
98, 8
Mean:
Median:
Range:
Lower Quartile:
Upper Quartile:

The values in this stem and leaf plot are (3, 8, 22, 32, 58, 98, 98).

Mean
Mean = Sum of all values
Number of values
= 3 + 8 + 22 + 32 + 58 + 98 + 98
7
= 319
7
= 45.6

Median
Median is the middle term when all the values are arranged in numerical order.
The values, in order, are (3, 8, 22, 32, 58, 98, 98).
32 is in the middle.

Range
Range = Max value of the data - Min value of the data
  = 98 - 3
  = 95

Lower Quartile
The lower quartile is the median of the first or lower half of the data values.
The lower half of the data values is (3, 8, 22).
The median of (3, 8, 22) is 8.

Upper Quartile
The upper quartile is the median of the second or upper half of the data values.
The upper half of the data values is (58, 98, 98).
The median of (58, 98, 98) is 98.

The answer is
Mean:
Median:
Range:
Lower Quartile:
Upper Quartile:

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