Answer
The fraction of the total distance to his grandmother's house that was travelled on Sunday = ¼
Step-by-step explanation
Let the whole distance be x
Hector's family travelled (5/8) of the distance to his grandmother's house on Saturday. That is, they travelled (5x/8)
The remaining distance = x - (5x/8) = (3x/8)
They then travelled (2/3) of the remaining distance on Sunday
(2/3) of the rest = (2/3) × (3x/8) = (x/4)
So,
The fraction of the total distance to his grandmother's house that was travelled on Sunday = ¼
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