Q7. Q8. Q9. Students in a botany course are carrying out an experiment to assess four brands of high potassium fertilizer which are claimed to aid early owering. Four students in the class each plant twelve similar sized cuttings of a hybrid petunia which is not usually propagated from seed. Each student divides their plants into four groups of three and applies a different brand of fertilizer to each group at the recommended dosage. Plants are all subjected to the same heat and light conditions in the greenhouse but there may be di'erences in the way each student waters and tip prunes their plants. Time to owering of the first petunia from each group of plants (in weeks) is shown in the following table. Stud t Brand of fertilizer en Flower Plus Floraboost Superpotash Floriado Kathy 8.75 9.50 8.50 11.50 Steven 9.50 4.00 8.50 11.00 Lee Ming 9.25 5.50 7.50 7.50 Irina 9.50 8.50 7.50 7.50 Using a 0.05 level of signicance, is there any evidence of a difference in the mean time to rst owering produced by the different brands? At the major shopping centre in Chatswood, NSW, there are several large chemist shops which compete for business, often through advertising discounted prices or specials. The following data shows prices for comparable items as shown on the shelves at three Chatswood chemist shops on 5 April 2008. Taft Hairspray 200g Il _ Claratyne 30pk 22 .99 22. 75 25.95 I_| _ L'Oreal Hair Colour -Crme Gloss 13.69 14.75 14.75 I5_| _ Nivea Shaving Ge1200m1 At the 0.05 level of signicance, determine if there is evidence of a di'erence in the mean prices for these products at the three chemist shops. A contractor wishes to see whether there is a difference in the time (in days) it takes two subcontractors to build three different types of homes. At a= 0. 05, analyses the data shown below. Home type Subcontractor I ll 1]] A 25, 28, 26, 30, 31 30, 32, 35, 29, 31 43, 40, 42, 4 9,48 B 15, 18,22,21, 17 21, 27,18,15,19 23, 25, 24,17,13