A) what is the difference between a sequence and a series? a series is an unordered list of numbers whereas a sequence is the sum of a list of numbers. a sequence is an ordered list of numbers whereas a series is an unordered list of numbers. a sequence is an unordered list of numbers whereas a series is the sum of a list of numbers. a series is an ordered list of numbers whereas a sequence is the sum of a list of numbers. a sequence is an ordered list of numbers whereas a series is the sum of a list of numbers.