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addict
11-16-2006, 08:40 AM
I had a series summation question in powerprep2 like S=1-1/2+1/3-1/4+1/5-1/6+1/7-1/8+1/9-1/10.

And the Q. Comparison was

Col A Col B
S 1/2

Please help me figure out this.

een
11-16-2006, 10:47 AM
Hello,addict!
IMHO S > 1/2.

You should present S like this
S={1-1/2}+{1/3-1/4+1/5-1/6+1/7-1/8+1/9-1/10}=
1/2+{1/3-1/4+1/5-1/6+1/7-1/8+1/9-1/10},
hence S=1/2+a, a=1/3-1/4+1/5-1/6+1/7-1/8+1/9-1/10 and we need to estimate part a,
1/3>1/10,
so the part a will be more than zero, so S>1/2.
All the best!
een

addict
11-16-2006, 07:06 PM
Got it. Thank you.