In a study of 223,067 cell phone users, it was found that 46 developed cancer of
ID: 2925887 • Letter: I
Question
In a study of 223,067 cell phone users, it was found that 46 developed cancer of the brain or nervous system. Assuming that cell phones have no effect, there is a 0.000235 probability of a person developing cancer of the brain or nervous system. We therefore expect about 53 cases of such cancer in a group of 223,067 people. Estimate the probability of 46 or fewer cases of such cancer in a group of 223,067 people. What do these results suggest about media reports that cell phones cause cancer of the brain or nervous system? (a) P(x46)= ____?
Explanation / Answer
here mean =np=223067*0.000235 =52.4207
std deviation =(np(1-p))1/2 =7.239
therefore from normal approximation:P(x46)= P(Z<(46.5-52.4207)/7.239)=P(Z<-0.8179)=0.2067
please revert for any clarification