CALCULATION:CONSIDERING the given values3/15 = 1/5 = 0.2,5/20 = 1/4 = 0.258/64 = 1/8 = 0.12525/1000 = 1/40 = 0.025So, 0.25 > 0.20 > 0.125 > 0.025∴ 25/1000 is the SMALLEST FRACTION.