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A series is given, in which one term is missing. Choose the correct alternatives from the given ones that will complete the series:

C4, B9, F25, C49, ? , D169

Solution

✅ Correct Option: 3

The numbers are squares of consecutive primes: 22,32,52,72,112,1322^2, 3^2, 5^2, 7^2, 11^2, 13^2, so the missing number is 121.

The letters split into two alternating chains. Odd positions give C, F, ? which is 3, 6, 9, so the letter is I. Even positions give B, C, D. Hence I121.

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