# Don't know if I've done this correctly.

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I know it's pretty straight forward and stuff but still not sure if I did it right.

I'm referring to question 5 btw.

And I have attached my answers as well.

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I got 2.19 as the mean and 1.56 as the sd using my calculator

check the values you put in and check your calculators in the right mode?

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I got 2.19 as the mean and 1.56 as the sd using my calculator

check the values you put in and check your calculators in the right mode?

Which values are you entering? The number of bathrooms or number of houses?

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Which values are you entering? The number of bathrooms or number of houses?

By Hand:

$Mean = \frac{\sum x}{N} = \frac{79 \times 1 + 31 \times 2 + 22 \times 3 + 10\times 4+5\times 5+13\times 6}{79+31+22+10+5+13}$

$= \frac{350}{160} = 2.1875$

$Std = \sqrt{\frac{\sum x^2}{N} - \mu ^2} = \sqrt{\frac{79 \times 1^2 + 31 \times 2^2 + 22 \times 3^2 + 10\times 4^2+5\times 5^2+13\times 6^2}{79+31+22+10+5+13} - 2.1875^2}$

$= \sqrt{\frac{1154}{160} - 2.1875^2} = 1.56$

By GDC (I used Ti84+)

, ,

There you go! Feel free to ask if there are any further questions.

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I got 2.19 as the mean and 1.56 as the sd using my calculator

check the values you put in and check your calculators in the right mode?

Which values are you entering? The number of bathrooms or number of houses?

I entered both

my data collum was no. of bathrooms and frequency was number of houses I think

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Which values are you entering? The number of bathrooms or number of houses?

By Hand:

$Mean = \frac{\sum x}{N} = \frac{79 \times 1 + 31 \times 2 + 22 \times 3 + 10\times 4+5\times 5+13\times 6}{79+31+22+10+5+13}$

$= \frac{350}{160} = 2.1875$

$Std = \sqrt{\frac{\sum x^2}{N} - \mu ^2} = \sqrt{\frac{79 \times 1^2 + 31 \times 2^2 + 22 \times 3^2 + 10\times 4^2+5\times 5^2+13\times 6^2}{79+31+22+10+5+13} - 2.1875^2}$

$= \sqrt{\frac{1154}{160} - 2.1875^2} = 1.56$

By GDC (I used Ti84+)

There you go! Feel free to ask if there are any further questions.

omg. thankyou so much.

I absolutely get it now!

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