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Question 9 6 pts During the battle of Verdun in WW1, French soldiers kept extensive track of daily German artillery usage. They would attempt to count the amount of artillery rounds the Germans fired. They knew that if the daily firings dipped, then the German Army was in the process of restocking, and there could be a window for a French counter-attack across "No Man's Land". They assumed a normal distribution for average daily firings and after counting for 30 days, the French concluded that the Germans fired an average of 672 shells with a standard deviation of 34 each day. The next day, they counted 654 shells fired. Calculate the Z-Score for 654 shells. HTML Editor BIA-A- IE3311 x 5 2 STT TT 12ot vad-Junior Blac png Quad-Junior Blac.png Quad-Junior Blac.png II

Answer 1

9)
Z = (X - mean)/sd = (X - 672)/34

z-score for 654
= (654 - 672)/34
= -0.5294

10)
P(X < 654)
= P(Z < -0.5294)
= 0.2983

odds = 0.2983 / (1-0.2983)
= 0.4251

11)
X = 584
z-score = -2.5882

12)
P(X < 584)
= P(Z < -2.5882)
= 0.0048

odds = 0.0048/(1-0.0048)
= 0.004823