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#1 2005-06-18 13:18:15

Lan P
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i need help

Hi all,
i need some help, Here the question:
1. What is the average (arithmetic mean) of 8, 7, 7, 5, 3, 2, and 2?
a. 3 4/7
b. 4 5/6
c. 4 6/7
d. 5
e. 6 4/5
I think the answer is A but the correct answer is C, i dont understand, please  to explain for me.

2. If F (4) = 0 and f (6) = 6, which of the following could represent f (x)?
a. 2/3x - 4
b. x + 2
c. x - 4
d. 3/2x + 6
e. 3x - 12
The correct is E. I dont understand, please help

#2 2005-06-18 15:49:31

im really bored
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Re: i need help

for the first part to find the mean just add all the numbers together like this:
8 + 7 + 7 + 5 + 3 + 2 + 2 = 34   then you divide that answer by the amount of terms or the amount of numbers, which is 7.   so then it would look like this:   34/7  which simplifys down to 4 6/7.

For the second problem think of f(x) to be just another way to put down a variable, "y"
so f(x) would just be y. so then for f (4) = 0 means that some function gives out the value of 0 when y = 4 and the second part f (6) = 6 means that the same function gives out a 6 when y = 6. so then you know that the function has to give out a 0 when y = 4, so then you can just put in 4 for all the x's untill one of them gives out the value of 0, in this case it is 3x - 12 where
3*4 - 12,  12 - 12, 0 , so that equation works for the value of 4. then you check it with the other part where y = 6 so 3*6 - 12,  18 - 12, which turns out a 6. so the equations works for both the values so it is the right answer.

#3 2005-06-20 12:21:06

Lan P
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Re: i need help

im really bored wrote:

for the first part to find the mean just add all the numbers together like this:
8 + 7 + 7 + 5 + 3 + 2 + 2 = 34   then you divide that answer by the amount of terms or the amount of numbers, which is 7.   so then it would look like this:   34/7  which simplifys down to 4 6/7.

i dont understand: your mean 46/7 or 4*6/7 but 4*6= 24 please explain again for me. Thanks

#4 2005-06-20 12:37:35

im really bored
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Re: i need help

What I meant is 4 and 6\7 as a mixed fraction simplyfied from the improper fraction of 34\7 where the 34 is divided by 7, 4 equal times with 6\7 left over, so it 4 and 6\7

Last edited by im really bored (2005-06-20 12:38:06)

#5 2005-06-21 13:56:57

Lan P
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Re: i need help

i see now. thank a lot

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