43 grade opc vs 53 grade opc?

The grade in cement mainly defile the average compressive strength after 28 days in mega pascals (Mpa) of at least three mortar cubes (area of face 50 cm squared) composed of one part cement, 3 parts of standard s and (conforming to IS 650:1966) by mass and P/4 (P is the percentage of water required to produce a paste of standard consistency as per IS standard) + 3 percentage (of combined mass of cement plus sand) of water, prepared, stored and tested in the manner described in methods of physical test for hydraulic cement.

721 hr not < 23 MPa for 43 grade, 27 MPa for 53 grade

1682 hrs not <33MPa for 43 grade, 37MPa for 53 grade

6724 hrs not <43MPa for 43 grade, 53 MPa for 53 grade