Question

Kacre On
+ HCl
Hei - Kel + Crels + Hoo + Cl​

Answer 1

Explanation:

It is given that mean of 100 observations is 50.

So, it will be something like this:-

\rm{\dfrac{x_1 +x_2 ...}{100} = 50}

100

x

1

+x

2

...

=50

So, what we need to do is, find the value of resulting mean.

But, here is a glitch.

50 is replaced by 150, so how we can rearrange it back?

We can do it!

\rm{\dfrac{x_1 +x_2 ...}{100} = 50}

100

x

1

+x

2

...

=50

\rm{x_1 +x_2 ...= 50 \times 100}x

1

+x

2

...=50×100

\rm{x_1 +x_2 ...= 5000}x

1

+x

2

...=5000

Now, we will add 150 to the 5000, because it is the new mean.

But, what will happen of that 50? It was already included!

Simple, we will subtract it.

5000 +150 = 5150

And, subtracting the already included replaced value,

5150 - 50 = 5100

So, resulting mean is 5100. Hence the answer.