Question

Identify the number that does not belong to the number series given below: 789, 645, 545, 481, 440, 429, 425

• A. 645
• B. 481
• C. 545
• D. 440
• E. 429

Hint:

Look for patterns in differences, squares, or multiples. Sometimes one number disrupts an otherwise consistent sequence.

Answer 1

The Correct Option is D

Step 1: Find the differences between consecutive terms: $789 - 645 = 144$, $645 - 545 = 100$, $545 - 481 = 64$, $481 - 440 = 41$, $440 - 429 = 11$, $429 - 425 = 4$.
Step 2: Observe the pattern: $144, 100, 64, 41, 11, 4$. These are not following a consistent pattern.
Step 3: Check squares: $12^2=144$, $10^2=100$, $8^2=64$, $7^2=49$ (but we have 41), $?$
Step 4: The number 481 appears to be the outlier as the difference after it breaks the pattern.
Step 5: Final Answer: The number that does not belong is 481.