Question

HERE IS THE QUESTION ⤴️⤴️⤴️♥️♥️TOPPERS❤❤


PLSSS HELP ME!!!

⭐⭐NOTE:-

⚪⚪ NO IRRELEVANT ANSWER!!❌❌
⭕⭕ NO WRONG ANSWER!! DON'T ANSWER IF U R NOT SURE!!✌✌

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Answer 1

Answer:

$f_1$ = 8

$f_2$ = 12

Step-by-step explanation:

Given :

Sum of all frequencies = 50

Men of the given data = 62.8

Solution :

Sum of all frequencies = 5 + $f_1$ + 10 + $f_2$ 7 + 8 = 50

⇒ 30 + $f_1+f_2$ = 50

⇒ $f_1+f_2=20$ ...(i)

Mean = $\frac{Sum \ of \ all \ observations}{Total \ number \ of \ observations} = \frac{\Sigma f_ix_i}{\Sigma f_i}$

⇒ $62.8 = \frac{(\frac{20+0}{2}) \times 5+(\frac{40+20}{2}) \times f_1+(\frac{60+40}{2}) \times 10+(\frac{80+60}{2}) \times f_2+(\frac{100+80}{2}) \times 7+(\frac{100+120}{2}) \times 8}{50}$

⇒ $62.8 = \frac{(\frac{20}{2}) \times 5+(\frac{60}{2}) \times f_1+(\frac{100}{2}) \times 10+(\frac{140}{2}) \times f_2+(\frac{180}{2}) \times 7+(\frac{220}{2}) \times 8}{50}$

⇒ $62.8 = \frac{(10) \times 5+(30) \times f_1+(50) \times 10+(70) \times f_2+(90) \times 7+(110) \times 8}{50}$

⇒ $62.8 = \frac{50+30f_1+500+70f_2+630+880}{50}$

⇒ $62.8 = \frac{30f_1+70f_2+2060}{50}$

⇒ $62.8 \times 50 = 30f_1 + 70f_2 + 2060$

⇒ $3140 = 30f_1 + 70f_2 + 2060$

⇒ $3140 - 2060=30f_1 + 70f_2$

⇒ $1080 = 30f_1 + 70f_2$

⇒ $10(108) = 10(3f_1+7f_2)$

⇒ $108 = 3f_1+7f_2$ ..(ii)

By subtracting 3 × (i) from (ii),

We get,

⇒ $(3f_1+7f_2)-3(f_1+f_2) = 108-3(20)$

⇒ $3f_1+7f_2-3f_1-3f_2= 108-60$

⇒ $4f_2=48$

⇒ $f_2=\frac{48}{4} = 12$

⇒ $f_2=12$

By substituting value of $f_2$ in (i),

We get,

$f_1+f_2=20$

⇒ $f_1+12=20$

⇒ $f_1=20-12$

⇒ $f_1=8$

________

∴ $f_1$ = 8

∴ $f_2$ = 12

________

Can you please stop calling for TOPPERS??,.

Answer 2

Solution :-

Given : Sum of all frequency = 50

Mean of frequency = 62.8

Case I : Sum of all frequency = 50

=> 5 + f1 + 10 + f2 + 7 + 8 = 50

=> f1 = 20 - f2 ______(i)

Case II : Mean of frequency = 62.8

=> Mean = Sum of all observations / Sum of frequency = ΣfiXi / Σfi

=> 62.8 = [(0 + 20)/2 × 5 + (20 + 40)/2 × f1 + (40 + 60)/2 × 10 + (60 + 80)/2 × f2 + (80 + 100)/2 × 7 + (100 + 120)/2 × 8]/50

=> 62.8 × 50 = [(20)/2 × 5 + (60)/2 × f1 + (100)/2 × 10 + (140)/2 × f2 + (180)/2 × 7 + (220)/2 × 8]

=> 3140 = 50 + 30f1 + 500 + 70f2 + 630 + 880

=> 3140 - 2060 = 30f1 + 70f2

=> 1080 = 30f1 + 70f2

=> 108 = 3f1 + 7f2

Now, From equation (i),

=> 108 = 3 (20 - f2) + 7f2

=> 108 = 60 - 3f2 + 7f2

=> 48 = 4f2

=> f2 = 12

Putting the value of f2 in equation (i) we get,

=> f1 = 20 - 12 = 8

Hence,

Value of f1 and f2 are 8 and 12 respectively.