In the word CONTEXTUAL, the first letter is swapped with the sixth, the second with the seventh, the third with the eighth, the fourth with the ninth, and the fifth with the tenth. After this rearrangement, which letter will be fourth from the right end of the new word?

Introduction / Context:
This problem is an example of a letter position and swapping puzzle. Aptitude tests often include such questions to check how accurately you can track positions during multiple interchanges. The challenge is to apply the swaps carefully and then count from the required side to identify the final letter at a specified position.

Given Data / Assumptions:
Original word: CONTEXTUAL.
Length of the word: ten letters.
Swaps to be made:
First letter with sixth letter.
Second letter with seventh letter.
Third letter with eighth letter.
Fourth letter with ninth letter.
Fifth letter with tenth letter.
We must find the letter that becomes fourth from the right in the new arrangement.

Concept / Approach:
The best approach is to write the word with indices, perform each specified swap step by step, and write down the resulting sequence. Once we have the final sequence, we then count from the right side to identify the required position. Accuracy in mapping indices is crucial, so a neat layout is strongly recommended when solving on paper.

Step-by-Step Solution:
Step 1: Write the letters with their positions: C(1), O(2), N(3), T(4), E(5), X(6), T(7), U(8), A(9), L(10). Step 2: Swap positions 1 and 6: C and X are exchanged, giving X, O, N, T, E, C, T, U, A, L. Step 3: Swap positions 2 and 7: O and T are exchanged, giving X, T, N, T, E, C, O, U, A, L. Step 4: Swap positions 3 and 8: N and U are exchanged, giving X, T, U, T, E, C, O, N, A, L. Step 5: Swap positions 4 and 9: T and A are exchanged, giving X, T, U, A, E, C, O, N, T, L. Step 6: Swap positions 5 and 10: E and L are exchanged, giving the final word X, T, U, A, L, C, O, N, T, E.

Verification / Alternative check:
The final arrangement after all swaps is XTUALCONTE. To find the fourth letter from the right, count from the rightmost letter. The letters from right to left are E (1), T (2), N (3), O (4), C (5), L (6), A (7), U (8), T (9), X (10). The fourth from the right is O. Recounting confirms that O is indeed fourth from the right, so the result is consistent.

Why Other Options Are Wrong:
N: This letter is third from the right, not fourth.
T: T occurs in the final word, but it is not at the fourth position from the right.
E: E is first from the right, so it does not satisfy the condition.
C: C is fifth from the right, not fourth.

Common Pitfalls:
Students often misapply swaps by changing letters instead of positions or by executing swaps in the wrong order. Another common mistake is counting from the left when the question clearly asks for a position from the right. Writing the letters carefully with indices and performing swaps one by one greatly reduces these errors.

Final Answer:
The letter that is fourth from the right after the described swaps is O.