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**morik****Member**- Registered: 2005-11-23
- Posts: 16

Hey guys,

Got a few questions here. I know they are probably no more than GCSE standard but still, I need and appreciate the help.

The scenario is I work for a computer repair company.

1. During January, the following faults were recorded

Number Fault

100 Hard Disk Drive

300 Power Supply

150 Operating System

200 Video Card

180 Wiring

30 Nil

Express each fault occurrence as a percentage of the total number of faults.

2. During the year the following numbers of computers were received for repair

Jan - 960

Feb - 900

Mar - 800

Apr - 750

May - 600

Jun - 650

Jul - 600

Aug - 400

Sep - 600

Oct - 800

Nov - 200

Dec - 150

1. What is the total number of computers received for repair?

2. What is the mean number received per month?

3. What is the median of the data above?

4. What is the mode of the data above?

Thanks for your time.

Morik

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**John E. Franklin****Member**- Registered: 2005-08-29
- Posts: 3,588

Is the Nil Fault an actual fault or a service call that was fixed some other way?

Do we count the Nil ones?

In second question, what does "mode" mean?

**igloo** **myrtilles** **fourmis**

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**mathsyperson****Moderator**- Registered: 2005-06-22
- Posts: 4,900

The mode is the most common number. Here, it is 600 because it appears three times. I'm quite surprised you didn't know that, John.

For the rest of 2:

1. Just add up all of the numbers for each month.

2. Take your answer to 1) and divide it by 12 (the number of months)

3. Arrange the numbers in order and pick the middle one. Here, that is halfway between the 6th and 7th ones, so just take the mean of those.

4. As above, it is 600 because it is the most common.

Why did the vector cross the road?

It wanted to be normal.

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**morik****Member**- Registered: 2005-11-23
- Posts: 16

Thanks for the help guys. As for the first question, "Nil" is an actual fault so must be counted.

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**John E. Franklin****Member**- Registered: 2005-08-29
- Posts: 3,588

Nil 3.125%

because 30 / (100+300+150+200+180+30) = 0.03125

Move decimal over two to the right to make a percent. .03125 is then 3.125% or 3 and 1/8 percent.

**igloo** **myrtilles** **fourmis**

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