GATE Data Science and Artificial Intelligence 2024 | Sample Paper | Question: 4

Question

The mean of the observations of the first $50$ observations of a process is $12$. If the $51$ $\text{st}$ observation is $18$, then, the mean of the first $51$ observations of the process is

• A. $12$
• B. $12.12$
• C. $12.36$
• D. $18$

   

Answer 1

We are given with 50 observations, whose mean is 12.

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NOTE : mean = ($\sum x$) / Total number of observations.

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So, $(\sum x) / 50 = 12$

$\sum x = 600$

Sum of 50 observation = 600.

$51^{th}$ observations is 18. Now, total number of observation becomes 51.

Sum of 51 observations = 618

Now, mean will become :

618 / 51 = 12.117647

$\simeq$ 12.12

Option B, is Correct Answer.