The word that describes the relationship between the letters in PEACH and HCAEP is "reverse order". Find the missing number in the sequence 46251 that follows the same rule.
P-E-A-C-H reversed becomes H-C-A-E-P.
4-6-2-5-1 reversed becomes 1-5-2-6-4.
The pattern is created in reverse order so we need to build the sequence up in the forward order.
Word example: PEACH → HCAEP (letters are reversed).
Number example: 46251 → reverse the digits → 15264