SOLUTION: Find x if the sequence m,x,n is an arithmetic Please help and explain how to Thank you in advance :)

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Question 1041231: Find x if the sequence m,x,n is an arithmetic
Please help and explain how to
Thank you in advance :)
Found 3 solutions by josgarithmetic, ikleyn, MathTherapy:
Answer by josgarithmetic(39618)   (Show Source):
You can put this solution on YOUR website!
You need a sensible description. You only have:
d may be common difference;

OR
Sequence for the first three terms is m, m+d, m+2d

Answer by ikleyn(52788)   (Show Source):
You can put this solution on YOUR website!
.
Find x if the sequence m,x,n is an arithmetic
Please help and explain how to
Thank you in advance :)
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If three numbers a, b and c form an arithmetic progression, then the middle number is half-sum of the two others: b = . Indeed, b = a+d and c = a+2d, then a + c = (a + a+2d) = 2a + 2d. Hence, = = a + d =b. Therefore, in your case, x = .

See the lesson One characteristic property of arithmetic progressions in this site.

Answer by MathTherapy(10552)   (Show Source):
You can put this solution on YOUR website!

Find x if the sequence m,x,n is an arithmetic
Please help and explain how to
Thank you in advance :)

In an AP with 3 terms, d or the common difference is calculated as: 2^nd term - 1^st term = 3^rd term - 2^nd term, or
x + x = n + m
2x = n + m