Question

The mean of 12 observations is 32 if one observation 10is deleted find the mean

Answer 1

$\huge\mathbb{SOLUTION:-}$

$\sf\underline{\blue{\:\: \:Given:-\:\:\:}}$

Mean of 12 observation is 32

$\boxed{\sf{Mean=\dfrac{sum\:of\: observation}{number\:of\: observation}}}$

• Let the observation be x

Now

$\sf\underline{\purple{\:\: \:Solution:-\:\:\:}}$

$\sf\implies \dfrac{x}{12}=32\\ \\ \sf\implies x=32\times 12\\ \\ \sf\implies x=384$

• The sum of observation is 384

• So one observation which is 10 removed
• Then new observation

$\sf \bullet 384-10= 374$

• So Our new mean

$\sf\implies mean=\dfrac{sum\:of\: observation}{No.\:of\: observation}\\ \\ \sf\implies mean=\cancel{\dfrac{374}{11}}\\ \\ \sf\implies mean=34$

So our new mean be

$\boxed{\sf{New\:Mean= 34}}$

Answer 2

given,

• Mean=32
• No of observation =12

The sum of observation =32×12=384

So one observation which is 10 removed

then,Remaining sum=384-10=374

Now,

No of observation =11

Mean=374/11

Mean=34