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Let Sk be sum of an indinite G.P whose f...

Let `S_k` be sum of an indinite G.P whose first term is 'K' and commmon ratio is `(1)/(k+1)`. Then `Sigma_(k=1)^(10) S_k` is equal to _________.

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To solve the problem, we need to find the sum of an infinite geometric progression (G.P.) for each value of \( k \) from 1 to 10, and then sum these results. ### Step 1: Identify the formula for the sum of an infinite G.P. The sum \( S \) of an infinite G.P. with first term \( a \) and common ratio \( r \) (where \( |r| < 1 \)) is given by: \[ S = \frac{a}{1 - r} \] ### Step 2: Substitute the values for \( S_k \) In our case, the first term \( a = k \) and the common ratio \( r = \frac{1}{k+1} \). Therefore, we can write: \[ S_k = \frac{k}{1 - \frac{1}{k+1}} \] ### Step 3: Simplify the expression for \( S_k \) Now, simplify the denominator: \[ 1 - \frac{1}{k+1} = \frac{(k+1) - 1}{k+1} = \frac{k}{k+1} \] Thus, we can rewrite \( S_k \): \[ S_k = \frac{k}{\frac{k}{k+1}} = k \cdot \frac{k+1}{k} = k + 1 \] ### Step 4: Find the summation \( \Sigma_{k=1}^{10} S_k \) Now we need to find: \[ \Sigma_{k=1}^{10} S_k = \Sigma_{k=1}^{10} (k + 1) \] This can be separated into two sums: \[ \Sigma_{k=1}^{10} S_k = \Sigma_{k=1}^{10} k + \Sigma_{k=1}^{10} 1 \] ### Step 5: Calculate \( \Sigma_{k=1}^{10} k \) The sum of the first \( n \) natural numbers is given by the formula: \[ \Sigma_{k=1}^{n} k = \frac{n(n + 1)}{2} \] For \( n = 10 \): \[ \Sigma_{k=1}^{10} k = \frac{10 \times 11}{2} = 55 \] ### Step 6: Calculate \( \Sigma_{k=1}^{10} 1 \) This sum simply counts the number of terms, which is 10: \[ \Sigma_{k=1}^{10} 1 = 10 \] ### Step 7: Combine the results Now combine the two sums: \[ \Sigma_{k=1}^{10} S_k = 55 + 10 = 65 \] ### Final Answer Thus, the value of \( \Sigma_{k=1}^{10} S_k \) is: \[ \boxed{65} \]

To solve the problem, we need to find the sum of an infinite geometric progression (G.P.) for each value of \( k \) from 1 to 10, and then sum these results. ### Step 1: Identify the formula for the sum of an infinite G.P. The sum \( S \) of an infinite G.P. with first term \( a \) and common ratio \( r \) (where \( |r| < 1 \)) is given by: \[ S = \frac{a}{1 - r} \] ...
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