Also, what is the difference with a population mean and a sample mean?

Thanks

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- Jun 23rd 2007, 05:15 AM #1

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## Mean

Hey,

Can you guys explain these questions:

60% of the mark is term work and 40% is exam

If yoiu receive a final mark of 76, and receive 70 on the exam, what is your term mark? (All marks are out of 100)

Can you guys explain how you would get the answer? Does it have something to do with weighted mean?

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The mean of a set of numbers is 26, What would the mean be if one of the numbers was increased by 10?

Thankyou

- Jun 23rd 2007, 05:29 AM #2

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- Jun 23rd 2007, 05:46 AM #3

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final = 0.6*term + 0.4*exam

so:

76 = 0.6*term + 0.4*70

rearranging:

term = (76 - 0.4*70)/0.6 = 80.

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The mean of a set of numbers is 26, What would the mean be if one of the numbers was increased by 10?

Thankyou

if one of the numbers is increased by 10 the new sum s'=s+10, and the

new mean:

mean'=s'/N=(s+10)/N = mean + 10/N

RonL

- Jun 23rd 2007, 05:48 AM #4

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- Jun 23rd 2007, 12:31 PM #5

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- Jun 23rd 2007, 12:47 PM #6

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- Jun 23rd 2007, 01:06 PM #7

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- Jun 23rd 2007, 01:40 PM #8

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- Jun 24th 2007, 07:38 AM #9

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- Jun 24th 2007, 07:52 AM #10

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- Jun 24th 2007, 11:29 AM #11

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- Jun 24th 2007, 01:10 PM #12

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