Apps. and Interpretation for IBDP Maths Ebook 1 | Page 228

Your Practice Set – Applications and Interpretation for IBDP Mathematics
Chapter
17
Statistics
SUMMARY POINTs
�
Relationship between frequencies and cumulative frequencies:
Data Frequency Data less than or equal to Cumulative frequency
10 f 10 f
1
1
20 f
2
20 f1�
f2
30 f
3
30 f1 � f2 � f3
� Measures of central tendency for a data set { x1 , x2, x3, , x n
} arranged in
ascending order:
x1 � x2 � x3 � � xn
1. x �
: Mean
n
2. The datum or the average value of two data at the middle: Median
3. The datum appear the most: Mode
218
SE Production Limited