The marking of time, and the language used in the times the Bible was written was not as exacting as modern english demands.
An example would be when someone replies to a question as to when something will happen in spanish with “Manana” it does not mean the literal translation of “Tomorrow” but rather some time soon. Three days in the tomb, can be interpreted as spanning over three days.
There is an old saying, “The translator is a liar.” Because translation is very tricky. You can translate literally from one language to another, but we all know that some words have more than one meaning. Sarcasm and other double meanings cannot always be translated. Local idioms also can be missed. So we have to be very careful when we put our own interpretation as correct, rather than a consensus of the Fathers, or the Teaching Authority of the Church/