In the following question, a simple increasing number series is given. Select the missing number from the series: 10, 12, 14, 16, 18, ?

Introduction / Context:
This is a basic arithmetic series question designed to test quick recognition of constant increments. The given series 10, 12, 14, 16, 18, ? increases steadily and is a typical example of questions that appear early in reasoning sections to build speed.

Given Data / Assumptions:

• Series: 10, 12, 14, 16, 18, ?
• Options: 22, 24, 20, 26.
• We assume a constant difference between consecutive terms.

Concept / Approach:
The best approach is to calculate the difference between consecutive terms. If the difference is the same, we have an arithmetic progression. We then add this common difference to the last known term to get the missing term.

Step-by-Step Solution:
Step 1: Compute differences.12 - 10 = 2.14 - 12 = 2.16 - 14 = 2.18 - 16 = 2.Step 2: Recognise the pattern.The series is an arithmetic progression with common difference 2.Step 3: Find the next term.Missing term = 18 + 2 = 20.

Verification / Alternative check:
With the missing term included, the full series is 10, 12, 14, 16, 18, 20. Every pair of consecutive terms differs by exactly 2, so the pattern is fully consistent and there is no irregularity at any step.

Why Other Options Are Wrong:
22: Would follow 18 with a jump of 4, breaking the constant difference of 2.24: Would skip several values and increase the difference to 6.26: Makes the difference 8, which is not supported by any earlier step in the series.

Common Pitfalls:
This kind of question is straightforward, but under exam pressure some students mistakenly add the wrong difference or misread the last term. A disciplined habit of checking differences sequentially helps avoid careless mistakes on very easy marks.

Final Answer:
The missing term that keeps the constant difference of 2 is 20.