Aptitude - Numbers - Discussion

Discussion Forum : Numbers - General Questions (Q.No. 57)

Numbers

57.

	1 -	1		+		1 -	2		+		1 -	3		+ ... up to n terms = ?
		n					n					n

1	n
2

1	(n - 1)
2

1	n(n - 1)
2

None of these

Answer: Option

Explanation:

Given sum

= (1 + 1 + 1 + ... to n terms)	-		1	+	2	+	3	+ ... to n terms
			n		n		n

= n -	n		1	+ 1		[ Ref: nth terms = (n/n) = 1]
	2		n

= n -	n + 1
	2

=	1	(n - 1)
	2

Discussion:

15 comments Page 2 of 2.

Richa said: 1 decade ago

Not getting it. Please explain more.

Gowry said: 7 years ago

Can anyone explain clearly? Please.

Vanitha said: 10 years ago

Can you please explain it clearly?

Atul said: 9 years ago

I think it should be n+1/2.

Madhur said: 9 years ago

More simple method.

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