Answer to Question #198801 in Statistics and Probability for Ali

Question

Repeated tests on the determination of human blood composition during a laboratory 

analysis are known to be normally distributed. Ten tests on a given sample of blood yielded the 

values 1.002, 0.958, 1.014, 1.009, 1.031, 1.048, 1.024, 1.019, 1.020. Find a 90 per cent 

confidence interval for true composition of the blood in repeated tests of the sample, and what is 

the margin of error?

 A random sample of fourty six funds averages a 16.9 per cent annual investment return for 

2001–2 with a standard deviation of 3.6 per cent annual return. The BSE Stock Index grew at an 

annual average rate of 16.3 per cent over the same period. Do these data show that, on the 

average, the mutual funds out-performed the BSE Stock Index during this period?