ten dry cells were taken from store and voltage tests gave the following results: 1.52,1.53,1.49,1,48,1.47,1.49,1.51,1.50,1.47,1.48 volts. the mean voltage of the cells when stored was 1.51v. assuming the population standard deviation to remain unchanged at 0.02v,
Given , mean say "x=1.51"
Let "H_o:\\mu_o\\ge1.51," The mean voltage of the cell greater than 1.51 volts.
and "H_a:\\mu_o <1.51" , The mean voltage of the cell is not greater than 1.51 volts.
Population mean, "\\mu=\\dfrac{14.94}{10}=1.494\n,\\text{ Population standard deviation }\n\\sigma=0.02"
Sample size, "n=10"
using t-test for independent sample
Test statistics-
"t=\\dfrac{x-\\mu}{\\frac{\\sigma}{\\sqrt{n}}}=\\dfrac{1.51-1.494}{\\frac{0.02}{\\sqrt{10}}}=0.9486"
The value of t at 5% level of significance and degree of freedom (n-1) i.e. 9 is 1.895.
Conclusion: As calculated value of t is less than the tabular value of 1.895. So Null hypothesis is accepted. The mean voltage of the cell greater than 1.51 volts.
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