Question

Average of 20, 30, 40 X is 40 find the value of x

Answer 1

Step-by-step explanation:

Question:-

Average of 20,30,40 & x is 40.

Find the value of x.

Answer:-

Given :-

All numbers = 20,30,40 & x.

Their mean = 40

To find :-

The value of x.

Process :-

We know that :-

Mean/Average = Sum of all terms/Total number of terms.

∴ Mean = 20+30+40+x/4

⇒40 = 90+x/4

⇒40×4 = 90+x

⇒160 = 90+x

⇒90+x = 160

⇒x = 160 - 90

⇒x = 70

∴ The value of x is 70.

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Hope it helps you....

#be brainly

Answer 2

Answer:

Given That

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• $: \red\implies \sf \pink{Numbers} - \purple{20, 30, 40 \: and X}$
• $:\red \implies \sf \pink{Average} - \purple{40}$

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To Find

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• $: \purple \implies\sf \red{Value \: of \: X}$

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Using Concept

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• ${:\purple\implies\sf\red{Formula\:of\:Average }}$

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Using Formula

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• $:\red \implies \sf \pink{Average} = \purple{\dfrac{Sum\: of\: All\: numbers}{Number\: of \:Unit } }$

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Full Solution

$: \red \implies\sf \pink{40 }=\purple{\dfrac{20 + 30+ 40+X}{4} } \\ \\ :\red \implies\sf \pink{40}= \purple{\frac{90 + x}{ 4} } \\\\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: : \red\implies \sf \pink{40 \times 4} = \purple{90 + x} \\ \\ \: \: \: \: \: : \red \implies \sf \pink{160} = \purple{90 + x} \\ \\: \red \implies \sf \pink{x} = \purple{ 160 - 90} \\\\: \red\implies \sf \pink{x} = \purple{70} \\ \\ \large\boxed{ \mathfrak\pink{x} = \purple{70}}$

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Therefore

The Value of x is 70..