Answer:
air for
is not a pair of equivalent fraction.
Step-by-step explanation:
Fraction of a ham sandwich left = 
Fraction of a turkey sandwich left = 
Now we find,
Fraction of sandwich that he eat.
Fraction of a ham sandwich Joseph eat = 
Fraction of a Turkey sandwich Joseph eat = 
Now the pair of fraction we have are
Pair 1: 
Pair 2: 
Now, Equivalent fraction are those fractions which has equal simplest form.
Clearly above pair of fractions are already in simplest form.
So, pair 1 of fraction are not equivalent fractions.
Therefore, Pair for
is not a pair of equivalent fraction.