Jon ate the same amount as Matt.
The two amounts that are the same are
and
.
We can't tell yet which person ate which of these two amounts.
Tommy ate more than Matt did.
The only amount more than
or
is
.
So Tommy must have eaten
of his brownie.
Brenda ate more than Craig ate.
The only amounts left are
and
.
One fourth is greater than
.
So Brenda must have eaten
of her brownie.
Craig must have eaten
of his brownie.
Matt's brownie was cut into more pieces than Jon's.
Matt must have eaten
, because that brownie was cut into 4 pieces.
Jon must have eaten
, because that brownie was cut into 2 pieces.