Possibly a hang up regarding the 28 day lunar cycle, being easily divided by 4.
In many cultures, the week days took the names or various gods.
Our English system largely follows Germanic traditions.
Monday moon
Tuesday Tiws day a one handed god
Wednesday Wodens day another god
Thursday Thors day god of thunder
Friday Freis a god
Saturday Saturn
Sunday Sun.
There is an ISO standard for the stating of the date, which is good.
And in which it is suggested that the week starts on Monday. But many religious disagree as is their wont.
Seven days in a week is more generally used than seven days in the week, except if in reference to a specific week such as 'the seven days in the week' when referring to a specific week, such as the week before Christmas.
There are 7 days in a week and there is 4 weeks in a month
"which" day of the week
5 days is one work week, but there are 7 days in a week.
7 days in a week?
There are seven days in a week.
there are 7 days in a week.
7 days in a week
There are not 5 days in a week. There are 7 days in a week. There are 5 days in the working week for most people, because we have a two day weekend.
There are 7 days in a week but only 5 days in a business week, also called a work week.
A week is 7 days. Therefore, a week and a half would be 10.5 days.
2/7 of a week would be two days since a week is seven days, two 'parts' of a week would be two days.