Directions: Find the missing term in the given series. 111, 221, 441, 881, ?, 3521
Reveal answer
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Directions: Find the missing term in the given series. 111, 221, 441, 881, ?, 3521
1760
1761
1759
1758
None of these
The pattern is: 111*2 - 1 = 221; 221*2 - 1 = 441; 441*2 - 1 = 881. Following this, 881*2 - 1 = 1762 - 1 = 1761. Checking the next term, 1761*2 - 1 = 3522 - 1 = 3521, which matches.
The differences between the consecutive terms are 110, 220, and 440, which forms a geometric progression where each difference is doubled. The next difference in this pattern is 880, and adding 880 to 881 gives 1761. This is confirmed because adding 1761 and 1760 yields 3521.