JEE Mains · Maths · STD 11 - 8. sequence and series
The sum of the first \(20\) terms common between the series \(3 +7 + 1 1 + 15+ ... ......\) and \(1 +6+ 11 + 16+ ......\), is
- A \(4000\)
- B \(4020\)
- C \(4200\)
- D \(4220\)
Answer & Solution
Correct Answer
(B) \(4020\)
Step-by-step Solution
Detailed explanation
Given \(n = 20;\,\,{S_{20}} = ?\) Series \(\left( 1 \right) \to 3,7,11,15,19,23,27,31,35,\) \(39,43,47,\) \(51,55,59...\) Series \(\left( 2 \right) \to 1,6,11,16,21,26,31,36,41,\) \(46,51,56,\) \(61,66,71.\) the common terms between both the series are \(11,13,51,71...\) Above…
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