The next term in the series 81, 54, 36, 24, ... is _________. A. 12 B. 16 C. 18 D. 10

GATE 2014 · General Aptitude · Number Series · medium

Answer: 16

1. Verify the common ratio: 54/81 = 2/3. 36/54 = 2/3. 24/36 = 2/3. All equal, confirming a geometric sequence with r = 2/3.
2. Compute the 5th term: Next term = 24 * (2/3) = 48/3 = 16. Option B.