Which pair(s) of expression are equal in value? Check all that apply
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Note: Since the symbols for greatest integer function (GIF) and least integer function (LIF) are not given, I will be using the words GIF and LIF in the solution
GIF x means largest integer less than or equal to x, and LIF x means least integer greater than or equal to x.
We need to determine which expressions are equal
Option 1: GIF 4.9 and LIF 3.1
GIF 4.9 = 3
LIF 3.1 = 4
Hence GIF 4.9 ≠ LIF 3.1
Option 2: GIF 15.2 and GIF 14.8
GIF 15.2 = 15
GIF 14.8 = 14
Hence, GIF 15.2 ≠ GIF 14.8
Option 3: GIF -6 and LIF -6
GIF -6 = -6
LIF -6 = -6
Hence, GIF -6 = LIF -6
Option 4: LIF -3.2 and LIF -2.6
LIF -3.2 = -2
LIF -2.6 = -1
Hence, LIF -3.2 ≠ LIF -2.6
Hence, only in Option C the pair of expressions are equal.