Solve Mean Number Problem: 2 Conditions & Gentle Push

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Ibrahim's problem involves two lists of numbers with means p and q. He claims that the mean of the combined list equals (p+q)/2, which requires one of two conditions to be true. The first condition is that the number of elements in both lists must be equal. The second condition remains unclear, but suggestions include the means being equal or both lists containing only positive values. The discussion emphasizes the need for clarity on the second condition to validate Ibrahim's assertion.
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hi, i have this mean number problem that appears on my past paper and am kinda stuck. would like a gentle push in the right direction :D thnx

Homework Statement



Ibrahim has two lists of numbers.
The mean of the numbers in the first list is p.
The mean of the numbers in the second list is q.

Ibrahim combines the two lists into one new list of numbers.

Ibrahim says "The mean of the new list of numbers is equal to \frac{p+q}{2}"

One of the two conditions must be satisfied for Ibrahim to be correct.

qu) Write down each of these conditions.

Homework Equations





The Attempt at a Solution



Condition 1: The number of numbers in list 1 must be the same as list 2.

Condition 2:?

I'm stuck, lol. i can't find a second condition. I have had a few ideas, such as the number of numbers being the same of the mean - but that didn't really owrk when i looked further into it.

I also, had the idea of the lists both being with only 1 number, but that is just one case of condition 1.

Would i be right in saying the list had to contain positive values? or something along those lines? I couldn't really decide whether or not that would be right.

I may may missed something obvious, yet inconspicuous, that i might have taken for granted?


just a lil push in the right direction will help :D thnx
 
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hi,
you go to a wrong way, how do you know the Condition 1

The number of numbers in list 1 must be the same as list 2.
 
Suppose the two means are the same.
 
oooo i see, thnx :D
 
I may may missed something obvious, yet inconspicuous,

:rolleyes:
this problem is not difficulty ,you can't find something you want because you
are live in water ,just like fish(as somebody said).
 
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