QUESTION 3 The manufacture of a particular handmade article lakes place in two stages The lime taken for the rstslage. say X1 . is approximately nurrnaily distributed with a mean of 40 minutes and a standard deviation of3 minutes The time taken for the second stage. say X2, is also approximately normally distributed, but with a mean of15 minutes and a standard deviation efd minutes, The times to mmplete the two stages of production are independently distnhuted The mean (i.e. expected value) and standard deviation of the total time, say Y, to manufacture the article are 0 5m : 55 and 50m : 25 O em=40 and 30m = 5 0 em = 55 and 30m = 5 0 Em : 40 and 30m : 25 QUESTION 4 Again referring to the prehabliity distribution information of Question (3}. the pmbabiilty of finishing an articie in less than 47.5 minutes is approximately (Hint: Note that the sum oftwe nerrnaily distributed randern variahies is also nermaliy distributed) 0 0.0653 0 0.4332 0 0.9332 0 0.1587