Question

If 1 + (1/2) + (1/3) + ... + (1/20) = k, then what is the value of (1/4) + (1/6) + (1/8) + ... + (1/40)?

A) k/2 B) 2k C) (k – 1)/2 D) (k + 1)/2

Answer 1

The solution is option b)2k

Answer 2

Answer:

(k-1)/2

Step-by-step explanation:

(1/2)+(1/30)+.............+(1/20)=k-1

and this series becomes 1/(n+1).........=k-1  now this is eq1

now take the other given condition:

(1/4)+(1/6).....+(1/20) now this equals to 1/(2n+2) which we can writw that

1/2(n+1)  which is 1/2 times of eq 1.

so the answer is (k-1)/2