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## Solutions to Week 11 Bio chem questions

 Page 114 number 4.73. X is the random variable telling how many of the 200 men become blind. The event that a man becomes blind is p=0.0067. The event that k men become blind is B(n,k) p k (1-p)^n-k. For k=2, this is 0.36 Page 114, number 4.74 Now p=0.0074. The event that at least 2 woman get blind is {X > 1}, which has probability 1- P[ X =1 or X=0 ] = 1-P[X=1]-P[X=0]=0.436 Page 114, number 4.82 Similar as before. The smallest value of k such that P[X less or equal to k] is greater or equal to 0.95 is k=8 beds. Page 114, number 4.83 P[X=4]=0.096 Page 147, number 5.6: P[X>140] = 0.212 Page 147, number 5.7: P[X<90] = 0.0446 Page 149, number 5.41: Only 53 percent fall in the normal range. Page 149, number 5.42: 0.9 percent of normal people should have values that are at lesat 1.5 times the upper limit of normal. Page 149, number 5.44: The probability is 0.00008 Page 161, number 5.61: The probability is 0.009

 Last update, 12/6/2001