rad = {34.6302, 10.0623, 6.94622, 26.3059, 52.6308, 27.1662, 80.0562, 799.3, 44.5997, 14.0357, 1000}; DeleteCases[rad, x_ /; 10 > x || x > 700] (* {34.6302, 10.0623, 26.3059, 52.6308, 27.1662, 80.0562, 44.5997, 14.0357} *) You need an urgent syntax surgery. (* lol *) Or using the converse, `Cases`: Cases[rad, x_ /; 10 <= x <= 700]