Alphanumeric series – fill in the missing pair. Sequence: U32, V29, __, X23, Y20, …

Introduction / Context:
In alphanumeric series, letters and numbers usually follow separate, simple rules. Solve each part independently (alphabetical steps and numeric steps), then recombine them at the same index to get the missing pair.

Given Data / Assumptions:

• Sequence: U32, V29, __, X23, Y20
• Letters: U, V, ?, X, Y
• Numbers: 32, 29, ?, 23, 20
• Expect constant steps: letters often move by +1; numbers often move by a fixed decrement.

Concept / Approach:

Determine the step in letters and numbers separately. For letters, check the next letter in the alphabet. For numbers, compute the difference between neighbors to see if it is constant.

Step-by-Step Solution:

Verification / Alternative check:

Check neighbors: V29 → W26 is −3 numerically and +1 alphabetically; W26 → X23 repeats the same pattern. The rule holds across the series.

Why Other Options Are Wrong:

W17 and Z17 have incorrect numbers; Z26 has the wrong letter step (skips ahead). Only W26 fits both independent tracks.

Common Pitfalls:

Coupling letter and number changes with the same step size or sign. Treat them as separate mini-sequences.

Final Answer:

W26