An hour is 60 minutes, there are 4 quarters in an hour. Therefore three quarters of a hour is 45 minutes.
Twelve quarters equals three 'wholes', or three units, or three dollars if you are talking about US currency.
That is 3.3 cups
Three quarters of a tonne.
There are three quarters in three quarters.
That depends what it is three quarters of. If it is three quarters of a foot, there are 9 inches. If it is three quarters of an inch, it is three quarters of an inch.
3/4 of 75.00 = 56.25