Fred is a human calendar. Although he has intellectual developmental disorder and cannot add two numbers correctly, when asked he can correctly calculate the day of the week for virtually any date named in the past or the future. Fred is best described as having .

Fred is described as having SAVANT SYNDROME.

Explanation: Savant syndrome can be defined as a condition in which an individual with significant mental disabilities is very gifted in another aspect of an activity such as playing the piano or mental arithmetic. Savant syndrome is a rare, but extraordinary.

Savant syndrome

Explanation:

Savant syndrome is a condition in which a person has a mental disability but excels in skills that are related to memory. Also, most of the people that have this disease can calculate the day of any date with precision. According to this, the answer is that Fred is best described as having savant syndrome.

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