PART 1

Two methods are compared to inoculate or infect a corn fungusstrain known as huitlacoche. In a first stage of the study, theexperimenter wants to determine which of the methods generates thehighest percentage of infection. The method A consists in cuttingthe tip of the ear to apply the strain, and in the method B thestrain is injected transversely. Of 41 ears inoculated with themethod A, 20 were infected, that is, they generated huitlacoche;Meanwhile, 38 ears of corn inoculated with the method B they becameinfected 27.

Cob	% Coverage (Texcoco)	% Coverage (Celaya)	Weight in grams (Texcoco)	Weigth in grams (Celaya)	Difference
1	60	95	122.6	231.8
2	40	100	182.74	346.74
3	95	70	203.45	231.41
4	55	40	84.03	141.49
5	40	35	128.46	149.69
6	20	100	31.85	291.28
7	10	30	12.81	86.03
8	10	100	57.05	158.74
9	55	100	145.83	167.25
10	15	100	49.49	120.89
11	35	25	103.66	19.7
12	25	15	95.05	22.08
13	70	85	125.02	137.02
14	20	15	40.57	28.76
15	20	30	19.36	24.87

Part 2

With respect to the problem described in part 1, the best method of inoculation was applied to two varieties of maize in two locations. Once the ear is infected, it is important to measure the final percentage of the surface of the ear that was covered by the fungus, as well as the weight in grams of the huitlacoche. The results for variety 2 of maize, obtained in 15 ears of Texcoco and in 15 ears of Celaya are the same as in the table in part 1.

a) Can we say that the percentage of coverage of the fungus is higher in Celaya than in Texcoco? Test the appropriate hypothesis for the means

b) Use a scatter diagram (graph type X-Y) to verify if there isa linear relationship between the percentage of coverage of the earwith grams of huitlacoche.

c) Ignore the coverage and test the equality of the average production of huitlacoche in the two locations.

d) It is evident that the greater the coverage, the greater theproduction of huitlacoche, would there be a way of knowing withthese data whether a similar production of huitlacoche in bothlocations corresponds to the same coverage? Argue your answer.

Note: The exercises must be solved in two ways. The first iswithout using the excel data analysis and the second using theexcel data analysis. Remember that you have to show step by stepexplaining clearly.