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## Homework Statement

The resistances of 50 resistors are measured and the results recorded are as follows:

Resistance x Frequency

*1.) 5 x 17,*

2.) 5.5 x 12,

3.) 6 x 10,

4.) 6.5 x 6,

5.) 7 x 5)

2.) 5.5 x 12,

3.) 6 x 10,

4.) 6.5 x 6,

5.) 7 x 5)

Calculate standard deviation of the measurements

## Homework Equations

## The Attempt at a Solution

Added up the frequences and got

**n = 50**

Multiplied the resistance by its weight or frequency and got the following:

**1.) 86**

2.) 66

3.) 60

4.) 39

5.) 35

2.) 66

3.) 60

4.) 39

5.) 35

then I added the values up and divided the result by the sum of the frequencies (n) to get the mean (cant do an x bar so I'll denote it as M)

**M = 5.7**

If I follow the standard deviation formula and add up all results of (x - m)

^{2}I get a really low number so if I then divide that really low number by n which is 50 I get something like 0.0049.

What am I doing wrong? Is the x of the formula resistance x frequency in this case since its weighted data Im dealing with?