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The variance 2 of the data [figure] is .
29
fi=22, fixi=0+2+15+12+60+36+51=176 x= 17622=8
fixi2=0+2+75+72+600+432+867=2048
2= fixi2 fi- x2= 204822-64
= 32011 29.09 29 (nearest integer)
Answer: 29
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