Question

If 'AIR' is coded as 'DLU', what is the code for 'PLANE'?

• A. SOEPH
• B. SPDQH
• C. SPDPG
• D. SODQH

Hint:

Compare AIR with DLU letter by letter to find a constant forward shift, then apply that same shift to every letter of PLANE.

Answer 1

The Correct Option is D

Step 1: Find the shift used to code AIR as DLU.
Write each letter of AIR next to its coded letter and compare their positions in the alphabet.
A (position 1) becomes D (position 4), a shift of \(4 - 1 = 3\).
I (position 9) becomes L (position 12), a shift of \(12 - 9 = 3\).
R (position 18) becomes U (position 21), a shift of \(21 - 18 = 3\).
Every letter moves forward by the same amount, 3 places, so the rule is: replace each letter with the letter that is 3 places later in the alphabet.

Step 2: Apply the same shift to each letter of PLANE.
P (16) plus 3 gives 19, which is S.
L (12) plus 3 gives 15, which is O.
A (1) plus 3 gives 4, which is D.
N (14) plus 3 gives 17, which is Q.
E (5) plus 3 gives 8, which is H.

Step 3: Put the coded letters together in order.
Reading the results in the same order as PLANE gives S, O, D, Q, H, so the code is SODQH.

Final Answer:
The code for PLANE is SODQH.
\[ \boxed{\text{SODQH}} \]