The mean life of 100 fluorescent light tubes produced by a company is computed to be 1570 hours with standard deviations of 120 hours.. The company claims that the average life of the tubes produced by the company is 1600 hours. Using the level of significance of .05 ,is the claim is acceptable?
A stenographer claims that she can take dictation at the rate of more than 120 words per minute
Of the 12 tests given to her she could perform an average of 135 words with a standard deviation of 40. Is her claim valid( =.01)
Significance of the difference between 2 observed proportion
During a country wide investigation the incidence of T.B was found to be 1%. In a college of 400 strength 5 students were reported to be affected by T.B where as in another college of 1200 strength 10 were found to be affected. Does this indicate any significant difference.
Ans: z =0.79 <1.96(Accept H0) H0: p1=p2
H1: p1 p2
Significance of the difference between 2 sample proportion when the proportion of the population is not known
During a country wide investigation about the incidence of T.B it was found that in a college of 400 strength 5 students were reported to be affected by T.B where as in another college of 1200 strength 10 were found to be affected. Does this indicate any significant difference( =.05)
Testing the significance of difference between two population means
For a sample of 100 labours from kerala ,the average wages is Rs.10.50 with S.D Rs. 1.50 . For a sample of 150 labours from Tamil nadu the corresponding figures are Rs. 8.00 and Rs.1.00 respectively. Can you conclude that the average wages in Kerala are more than that of the workers in Tamil Nadu?( =.05)