Giovanna used the calculations below to determine the height of a stack of 7 books that are each 2 and StartFraction 5 over 8 EndFraction inches thick. What was her error?
7 (2 and StartFraction 5 over 8 EndFraction). 7 (2 + StartFraction 5 over 8 EndFraction). 14 + StartFraction 5 over 8 EndFraction. 14 and StartFraction 5 over 8 EndFraction