These round to a multiple rather than to decimal places:
=CEILING(number, significance) rounds up to the next multiple: CEILING(27,12) is 36, three cases of 12.=FLOOR(number, significance) rounds down: FLOOR(1.37,0.25) is 1.25.=MROUND(number, multiple) rounds to the nearest multiple: MROUND(17.4,5) is 15.
With negative numbers, FLOOR goes further from zero (FLOOR(-7.5,2) is -8) and CEILING goes toward zero. Newer Excel also has CEILING.MATH and FLOOR.MATH, with extra options for negatives.