# How to add fractions?

i dont know how to add 1/100+1/101+1/102+...+1/200

Does it have a formula?

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- roderick_youngLv 710 years agoFavorite Answer
That's called a Harmonic Series, and you can look it up in Wikipedia.

There's no simple formula for the sum of a harmonic series, but an approximation for the sum of the first n terms of the series 1/k is ln(k+1). So you could go ln(201) - ln(100) to get pretty close to the answer.

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- 10 years ago
Use this formula :

Sn = n [2a+ (n-1)b ] / 2

where,

Sn : The sum of arithmatic series

a = The 1st value of the series

b = the difference between two close series

and we get,

n = 201

a = 1/100

b = 1/101 - 1/100 = 0,1/1010

substitute the value above to the formula,

So, we get the Sn = 4,0009

Source(s): My lesson in Senior High School- Login to reply the answers

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