SOLUTION: In an a.p the sum of the squares of the five consecutive series is 20time the square of the middle term,and the product of the five terms equals to 80.What is the middle term.

Algebra.Com
Question 1076783: In an a.p the sum of the squares of the five consecutive series is 20time the square of the middle term,and the product of the five terms equals to 80.What is the middle term.

Answer by ikleyn(52787)   (Show Source): You can put this solution on YOUR website!
.
Let "a" be the middle term of the AP, and "d" be the common difference.
Then you have these equations

 = ,    (1)    and

 = .             (2)


Simplify (1) and (2):

 =           (1')     and
 =     (2')


Simplify (1'):

 = ,   which is the same as   = ,  which is the same as

 = .               (1'')


Then (2') becomes (after substitution (1'') )

 = ,   or

 = ,   or

 =  = .


Then a =  = 2.


Answer.  The middle term under the question is 2.

Solved.



RELATED QUESTIONS

If the sum of the terms of an arithmetic series is 234, and the middle term is 26, find... (answered by jim_thompson5910)
An A.P consists of 11 terms.the middle term is 30.find the sum of the series? (answered by richard1234)
Find the sum of 15 terms of an arithmetic series if the middle term is 92 (answered by greenestamps)
Find the sum of 15 terms of an arithmetic series if the middle term is... (answered by MathLover1)
The middle term of an arithmetic series of 31 terms is 50.determine the sum of the... (answered by ikleyn)
The first three terms of an arithmetic series have a sum of 24 and a product of 312. What (answered by Edwin McCravy)
In a geometric series, the 9th term is equal to 8 times the 6th term, while the sum of... (answered by robertb)
Determine the sum of the first 15 terms of an arithmetic series if the middle term is... (answered by rothauserc)
the sum of the squares of five consecutive a.p is 55,and their product is 120.what are... (answered by ikleyn)