Question
Question: If the sum of the first ten terms of the series is (13/5) + (13/5) + (13/5) + 4 + (13/5) +…, is (16/...
If the sum of the first ten terms of the series is (13/5) + (13/5) + (13/5) + 4 + (13/5) +…, is (16/5)m, then m is equal to:
Given the ambiguity of the question, and assuming it refers to a similar series pattern as in the related problem, m = 101.
Solution
The original question is ambiguous and likely contains a typo. The phrasing "If the sum of the first ten terms of the series is (13/5) + (13/5) + (13/5) + 4 + (13/5) +…, is (16/5)m" has two "is" clauses, leading to confusion and an undefined series.
Assuming the question intended to represent a series similar to the one in the related problem:
(153)2+(252)2+(351)2+42+(454)2+....
Which can be written as:
(58)2+(512)2+(516)2+(520)2+(524)2+....
The general term can be represented as (54(n+1))2.
The sum of the first 10 terms is:
S10=∑n=110(54(n+1))2=2516∑n=110(n+1)2
Let k=n+1, then:
S10=2516∑k=211k2
Using the formula for the sum of squares: ∑k=1Nk2=6N(N+1)(2N+1)
∑k=211k2=(∑k=111k2)−12=611×12×23−1=506−1=505
Therefore:
S10=2516×505
Given S10=516m:
2516×505=516m
Solving for m:
m=5505=101
Thus, m=101.