Multiple choice

Find the wrong number in the following number series.\newline15\quad72\quad363\quad1815\quad9063\quad45312\quad226563

  1. $9036$
  2. $1815$
  3. $9063$
  4. $226563$
  5. $72$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In the series 15, 72, 363, 1815, 9063, 45312, 226563, the pattern is: multiply by 5, then subtract 12. Checking: 15×5-12=63 (not 72). 72×5-12=348 (not 363). 363×5-12=1803 (not 1815). The pattern is multiply by 5, then subtract 12, but 1815 doesn't fit correctly. Let's recalculate: 363×5=1815, 1815-12=1803. So 1815 should be 1803. Or if 1815 is correct, then the rule is simply ×5: 15×5=75 (not 72). The pattern is inconsistent. Checking: 15×5-3=72, 72×5-? 72×5=360, 363=360+3. The pattern seems to be ×5 then alternating -3 and +3. 15×5-3=72, 72×5+3=363, 363×5-3=1812 (not 1815). So 1815 is wrong.

Keep practicing — related questions