Presently, the mean life expectancy ofa rare strain of bacteria is l2 hours A scientist claims...

Presently, the mean life expectancy ofa rare strain of bacteria is l2 hours A scientist claims that she has developed a medium and therefore disagrees with this hy pothesis that it is not 12 hours. The scientist tests 25 cultures and finds that they have a mean life of 15.25 hours with s 2 hour. Do these results show that the medium is effective in increasing the bacteria's life expectancy? (Use a-1%) a. State the null and alternative hypothesis b. Determine and draw the hypothesis test model (Label everything) Determine the critical value(s) and test statistic d. Determine the conclusion.

Expert Solution

Let denotes the mean life expectancy of these bacteria.

There is sufficient evidence to support the claim that the medium is effective in increasing the bacteria's life expectancy

orchestra answered 2 years ago

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