Question

Choose the correct alternative that will continue the same pattern and replace the question mark (?) in the series 7, 27, 107, 427, ?

• A. 1262
• B. 1707
• C. 827
• D. 2107

Hint:

If the numbers in a series grow rapidly, always start by checking for a multiplication pattern before looking at differences.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
This is a number series question where each subsequent term is derived from the previous term using a specific mathematical operation.
Step 2: Key Formula or Approach:
Check for multiplication and addition/subtraction patterns: $T_{n} = T_{n-1} \times k \pm d$.
Step 3: Detailed Explanation:
Let's find the relationship between the numbers:
1. $7 \rightarrow 27$: $(7 \times 4) - 1 = 28 - 1 = 27$
2. $27 \rightarrow 107$: $(27 \times 4) - 1 = 108 - 1 = 107$
3. $107 \rightarrow 427$: $(107 \times 4) - 1 = 428 - 1 = 427$
The pattern is to multiply by 4 and subtract 1.
4. Next term: $(427 \times 4) - 1 = 1708 - 1 = 1707$.
Step 4: Final Answer:
The next number in the series is 1707.