Multiple choice

Find the missing number in the sequence. 129 132 123 150 69 ?

  1. 322

  2. 302

  3. 332

  4. 312
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This series follows an alternating pattern: add 3 (129+3=132), subtract 9 (132-9=123), add 27 (123+27=150), subtract 81 (150-81=69), add 243 (69+243=312). The added/subtracted numbers are powers of 3: 3^1, -3^2, 3^3, -3^4, 3^5, with alternating signs.

Keep practicing — related questions