I too get the (wrong) answer as given in the publication. For the peach -> mango example also chatGPT gives incorrect answer.
Use a to substitute e, n to substitute a, g to substitute c, o to substitute h, m to substitute p. Then,
how to spell peach under this rule?
If we use the given substitutions to spell the word "peach", it would become "hmngn".
To explain further, "p" becomes "m" due to the substitution of "p" with "m". Similarly, "e" becomes "a" due to the substitution of "e" with "a". The letter "a" then becomes "n" due to the substitution of "a" with "n". The letter "c" in "ch" becomes "g" due to the substitution of "c" with "g". Finally, "h" becomes "o" due to the substitution of "o" with "h". Therefore, the resulting word is "hmngn".
This is a bad thing for the average Joe.