? = 5, ? = 4 ; calculate P(0 < x < 8) This is the same as P(x < 8) - P(x < 0). P(x < 8) [URL='https://www.mathcelebrity.com/probnormdist.php?xone=8&mean=5&stdev=4&n=1&pl=P%28X+%3C+Z%29']using our calculator[/URL] is 0.773373 P(x < 0) [URL='https://www.mathcelebrity.com/probnormdist.php?xone=0&mean=5&stdev=4&n=1&pl=P%28X+%3C+Z%29']using our calculator[/URL] is 0.10565 So we have 0.773373 - 0.10565 = [B]0.667723[/B]