Please help answer these problems

1.find the value of 1/(4x9) + 1/(9x14) + 1/(14x19) + ........ + 1/(1999x2004)

2.find the value of 1/3 + 1/6 + 1/10 + 1/15 + 1/21 + ....... + 1/300

(Headbang)I'm waiting..... Thank you

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- Mar 21st 2008, 12:02 AMcdesianifraction problems
Please help answer these problems

1.find the value of 1/(4x9) + 1/(9x14) + 1/(14x19) + ........ + 1/(1999x2004)

2.find the value of 1/3 + 1/6 + 1/10 + 1/15 + 1/21 + ....... + 1/300

(Headbang)I'm waiting..... Thank you - Mar 21st 2008, 06:57 AMteuthid
what level of math did this problem come from? Would it make sense to you if I told you that the first sum could be expressed as ?

- Mar 21st 2008, 08:50 AMcdesiani
This problem was one of the problems in Math Olympiad for the elementary school. The time allocated for the problems is about 5 minutes. So there must be simple but logical answer. Please help...

(Crying) - Mar 21st 2008, 09:40 AMteuthid
Sorry, I can't think of anything that could be done by an elementary student in 5 minutes.

- Mar 21st 2008, 05:29 PMSoroban
Hello, cdesiani!

Elementary school?

Perhaps*very bright*elementary students who have mastered Algebra

. .**and**know some clever (sneaky) tricks . . .

Quote:

1) Find the value of: .

We note that: .

We have: .

. . . . . .

. . . . . .

Quote:

2) Find the value of: .

We note that: .

We have: . . . . . .

. . . . .

. . . . .

. . . . .

By sixth grade I had mastered tying my shoelaces and finding my mittens.

. - Mar 23rd 2008, 06:58 AMcdesianiThank you, it's solved!!
Wow, what a beautiful way to solve such a difficult problem!

Thank you so much!

(Rofl) - Apr 11th 2008, 02:08 PMsamlexii1403@yahoo.com
WELL........

I CAN NOT HELP U I DO NOT NO HOW 2 DO IT ETHER !!!!(Emo)

*****SORRY!!!!!!!!!!*****

- Apr 11th 2008, 02:09 PMMoo
Hi,

Please be nice with my eyes (Crying)