Question

Mean of two numbers is 10. If one is 4 then other number what.​

Answer 1

Given :-

• Mean of two numbers is 10
• One number is 4

To Find :-

• What is the other number ?

Formula Used :-

♣️ Mean Formula :

$\bigstar \: \color{magenta} \boxed{ \bf Mean = \frac{Sum \: Of \: Observations}{Number \: of \: Observations} } \: \color{black} \bigstar$

Solution :-

Given :

• Mean of two numbers = 10
• One number = 4

Let,

• Other number = x

According to the question by using formula we get,

$\displaystyle\sf \implies \: Mean = \frac{Sum \: Of \: Observations}{Number \: of \: Observations}$

$\displaystyle\sf \implies \: 10 \: = \: \frac{4 + x}{2} \:$

By Cross Multiplication :

$\displaystyle\sf \implies \: 10 \times 2 \: = \: 4 + x$

$\displaystyle\sf \implies \: 20 \: = \: 4 + x$

$\displaystyle\sf \implies \: 20 - 4\: = \: x$

$\displaystyle\sf \implies \: 16\: = \: x$

$\displaystyle\bf \implies \: \red{ x = 16 }$

∴ The other number is 16 .

$\:$

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Answer 2

$\large \mathfrak \purple {☬ Mean \: Formula :} \\\color{yellow} \boxed{ \bf Mean = \frac{Sum \: Of \: Observations}{Number \: of \: Observations}}\\\large \mathfrak \purple{Solution :-} \\\large \mathfrak \purple{Given :} \\\sf \red{ Mean \: of \: two \: numbers = 10} \\ \sf \red{ One \: number = 4 }\\\sf\red{ Let,Other \: number = x }\\\sf \red{According \: to \: the \: question \: by \: using \: formula \: we \: get,} \\ \displaystyle\sf \red{ \implies \: Mean = \frac{Sum \: Of \:Observations}{Number \: of \: Observations}} \\\displaystyle\sf \red{ \implies \: 10 \: = \: \frac{4 + x}{2}}\\\displaystyle\sf \red{By Cross Multiplication :} \\\displaystyle\sf \red{ \implies \: 10 \times 2 \: = \: 4 + x}\\\displaystyle\sf \red{ \implies \: 20 \: = \: 4 + x} \\\displaystyle\sf \red{ \implies \: 20 - 4\: = \: x} \\\displaystyle\sf \red{ \implies \: 16\: = \: x}\displaystyle\bf \blue{ \implies x = 16 } \\\sf \red{∴ The \: other \: number \: is \: 16 .}$