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MathsMediumMCQ2018 ยท 16 Apr Online

Q66.The sum of the first 20 terms of the series 1 + 23 + 47 + 158 + 1631 + โ€ฆ is (1) 39 + 1 (2) 38 + 1 219 220 (3) 38 + 1 (4) 39 + 1 219 220 is

What This Question Tests

This question tests the ability to recognize a complex pattern in a series that can be rewritten to reveal a geometric progression, whose sum then needs to be calculated for a specified number of terms.

Concepts Tested

Pattern recognition in seriesGeometric Progression (G.P.)Sum of G.P.

Formulas Used

Sum of G.P. S_n = a(r^n - 1)/(r - 1)

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