Letter Coding: SHOES to Number Sequence

This problem involves a letter-to-number coding technique. The relationship between the word "SHOES" and the number "19815519" is based on the alphabetical position of each letter in the word. We need to apply the same logic to the word "SHIRT".

Step 1: Analyze the SHOES Example

Map each letter of "SHOES" to its position in the English alphabet:

• S is the 19^th letter.
• H is the 8^th letter.
• O is the 15^th letter.
• E is the 5^th letter.
• S is the 19^th letter.

Concatenating these positions gives the number: $19 \mathbin{|} 8 \mathbin{|} 15 \mathbin{|} 5 \mathbin{|} 19 = 19815519$. The vertical bar symbol is used here just for separation illustration; the actual process is direct concatenation.

Step 2: Apply Logic to SHIRT

Map each letter of "SHIRT" to its alphabetical position:

• S is the 19^th letter.
• H is the 8^th letter.
• I is the 9^th letter.
• R is the 18^th letter.
• T is the 20^th letter.

Step 3: Calculate the Result for SHIRT

Concatenate the positions obtained in Step 2:

The resulting number is $19891820$.

Step 4: Match with Options

The calculated number $19891820$ matches Option 4.