Question

Find the wrong term in the sequence.

$121,143,165,186,209$

• A. $143$
• B. $165$
• C. $186$
• D. $209$

Answer 1

Answer: (C)

$186$

$121\stackrel{+22}{\to }143\stackrel{+22}{\to }165\stackrel{+22}{\to }\left[187\right]\stackrel{+22}{\to }209$

The difference between the consecutive numbers is $22$ except $186-165=21.$

Therefore, the wrong term is $186$ and should be replaced by $187.$
Answer is option $C.$