Mod 1,2 Review - Question 14

Part (b) X = 680. Z = 2.35

Part (c). When X = 570, the Z-score is Z = (570 - 480) / 85 = 1.06. P( Z > 1.06 ) = 0.145. Click on the blank circle below (next to normaldist(0,1)) to see the graph for part (c). The probability is the green area.

Part (d). When X = 420, the Z-score is Z = (420 - 480) / 85 = - 0.71. P( Z < -0.71 ) = 0.239. Click on the blank circle below (next to normaldist(0,1)) to see the graph for part (d). The probability is the red area.