can anyone give me the answer of this question using step deviation method those who will give me the answer I will definitely mark it as brainliest please help me
Answers
Answer:
f₁ = 28, f₂ = 24
Step-by-step explanation:
x f fixi
10 17 170
30 f₁ 30f₁
50 32 1600
70 f₂ 70f₂
90 19 1710
--- --------------------
120 30f₁ + 70f₂ + 3480
(i)
Given, Mean = 50.
⇒ (30f₁ + 70f₂ + 3480)/120 = 50
⇒ (30f₁ + 70f₂ + 3480) = 6000
⇒ 30f₁ + 70f₂ = 2520
(ii)
⇒ 17 + f₁ + 32 + f₂ + 19 = 120
⇒ f₁ + f₂ = 120 - 68
⇒ f₁ + f₂ = 52
On solving (i) * 30 & (ii), we get
30f₁ + 70f₂ = 2520
30f₁ + 30f₂ = 1560
--------------------------------
40f₂ = 960
f₂ = 24
Substitute f₂ = 24 in (i), we get
⇒ 30f₁ + 70f₂ = 2520
⇒ 30f₁ + 70(24) = 2520
⇒ 30f₁ + 1680 = 2520
⇒ 30f₁ = 840
⇒ f₁ = 28
Hence, f₁ = 28 and f₂ = 24
Hope it helps!
Here mean=50
we know that, mean=sum of fixi devided by�sum of fi
here x=10 30 50 70 � 90
�f= 10 � f1 �32 �f2��19
sum of fi = 120
xi� fi � xifi
10 17 170
30 f1 30f1
50 32 1600
70 � f2 70f2
90 19 1710
Ʃfi=120 Ʃfixi=3480+70f2+30f1
so , 68+f1+f2=120
Mean=
50=
120x50=
6000-3480=
2520=
2520=10(7f2+3f1)
252=7f2+3f1------------(1)
68+f1+f2=120
120-68=f1+f2
52=f1-f2--------(2)
By substitution method-
252=7f2+3f1------------(1)
� 52=f2 - f1--------(2)
Multiplying eq.( 2) from 3 to substitute f1
252-52=7f2-3f2+3f1-3f1
We get,
200=4f2
50=f2
Putting value of f2 in eq. (2)
52=50-f1
2=f1
Value of f1=2 and f2=50
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