Question

A sample of 26 bulbs give a mean of 990 hours with a SD of 20 hours the manufacturer claims that the mean life 1000 hours sample not up to standard

Answer 1

Answer:

Given n=26

=990

1 - 1000 and S.D. fe, s=20 Null Hypothests Ho: μ = 10000

Alternative thy pathesis: th: M (1000

(left one tailed

test)

(Since it is given below standard)

level of significance a = 0.05 t tabulated value with 25 dereces of freedom for left tailed test is 1-708

• Test Statistic teal 9904000 =x-u /2
• $2 \sqrt{n - 1}$
• -2-5

20

Conclusion:

Sinal teall value> to value. We reject to. The Sample is not upto Standard,