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Find mean, median and mode for the following dataClass:-1-1011-2021-3031-4041-5051-6061-7071-8081-9091-100frequency:-37131712108866 |
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Answer» Answer: Classes x i
f i
f i
x i
c.f 0−20 10 6 60 6 20−40 30 8 240 14 40−60 50 10 500 24 60−80 70 12 840 36 80−100 90 6 540 42 100−120 110 5 550 47 120−140 130 3 390 50 ∑f i
=50 ∑f i
x i
=3120 ⇒ Mean= ∑f i
∑f i
x i
= 50 3120
=62.4 ⇒ N=50 and 2 N
=25 ∴ Median class =60−80 l= lower LIMIT of the modal class h= size of the class intervals f= frequency of the modal class f 1
= frequency of the class preceding the modal class f 2
= frequency of the class succeed in the modal class. ⇒ Here, l=60,f=12,cf=24,h=20. ⇒ Median=60+ 12 25−24 ×20 ⇒ Median=60+ 12 20 =61.66 ⇒ Modalclass=60−80 ⇒ l=30,f=12,f 1 =10,f 2 =6,h=20 Mode=l+ 2f−f −f 2 f−f 1 ×h ⇒ Mode=60+ 2×12−10−6 12−10 ×20 ⇒ Mode=60+5=65 |
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