SOLUTION: The 5th term of an arithmetic progression is three times the first term.find the sum of the first eight terms of the progression given that a quarter of the fifth term is 9
Algebra.Com
Question 870009: The 5th term of an arithmetic progression is three times the first term.find the sum of the first eight terms of the progression given that a quarter of the fifth term is 9
Answer by mananth(16946) (Show Source): You can put this solution on YOUR website!
The 5th term of an arithmetic progression is three times the first term.find the sum of the first eight terms of the progression given that a quarter of the fifth term is 9
let first term be a
and common difference be d
t5 = 3a
(1/4)t5 =9
t5=36
3a=36
a=12
t5=a+4d
36=12+4d
24=4d
6=d
a=12,d=6
Sn = (n/2) (2a+(n-1)d)
S8=(8/2)(2*12+(7*6))
=4*(14+13)
=(4*27)
=108
RELATED QUESTIONS
In an arithmetic progression, the sum of the first ten terms is 50 and the 5th term is... (answered by MathTherapy)
In an arithmetic progression, the sum of the first ten terms is 50 and the 5th term is... (answered by MathLover1,MathTherapy)
The fifth term of an arithmetic progression is three times the second term,and the third... (answered by ikleyn)
A geometric progression has 6 terms. The first term is 192 and the common
ratio is 1.5.... (answered by greenestamps)
A geometric progression has six terms. The first term is 486 and the common ratio is ;.... (answered by greenestamps)
The first and the last term of an arithmetic progression are 9 and 93.If the sum of the... (answered by mananth,stanbon)
The ninth term of an arithmetic progression is 52 and the sum of the first twelve terms... (answered by srinivas.g)
The first term of an Arithmetic progression is 3, find the common difference if the sum... (answered by josgarithmetic,MathTherapy)
The fifth term of an arithmetic progression is 24 and the sum of the first tenth terms is (answered by josgarithmetic)