Goodness of fit

[ofra]

Hi, i need to answer this question:

1.      You were asked to verify that the percentage of infected flies in the area is not more than 10%. Your budget allows to test up to 160 flies.

Below are the results of 40 sets of 4 flies each that show how many infected flies were found in each set:

number of infected            Number of samples

0                                        20

1                                        18

2                                        1

3                                         1

4                                        0

1.1. What test should you use?

1.2. What are your hypotheses?

1.3. What is your conclusion?

 

I think i should do chi square goodness of fit but i'm not sure how to build the expected column, since the 10% of the sets is different than 10% from 160 flies... not sure how to distribute them between the 4 infected categories (1,2,3,4). Does anyone have any idea? Thanks!

[fuzzylogician]

Hi there, this looks like a homework question. This site is not about helping students with homework but about discussing grad school applications, grad school life, etc. Please contact a teacher or TA about your question.