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Select the number from among the given options that can replace the question mark (?) in the following series.549, 525, 477, 405, 309, ?
Question

Select the number from among the given options that can replace the question mark (?) in the following series.

549, 525, 477, 405, 309, ?

A.

145

B.

167

C.

189

D.

139

Correct option is C

Given Series: 549, 525, 477, 405, 309, ?
Find the differences between consecutive terms
549−525=24
525−477=48
477−405=72
405−309=96
The differences are increasing in multiples of 24:
24, 48, 72, 96.
The next difference should be 96 + 24 = 120.
309−120=189.
Final Answer: 189

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