Question

Reliance on solid biomass fuel for cooking and heating exposes many children from developing countries to high levels of indoor air pollution. An article presented information on various pulmonary characteristics in samples of children whose households in India used either biomass fuel or liquefied petroleum gas (LPG). For the 755 children in biomass households, the sample mean peak expiratory flow (a person's maximum speed of expiration) was 3.2 L/s, and the sample standard deviation was 1.2. For the 757 children whose households used liquefied petroleum gas, the sample mean PEF was 4.46 and the sample standard deviation was 1.94. (a) Calculate a confidence interval at the 95% confidence level for the population mean PEF for children in biomass households and then do likewise for children in LPG households. (Round your answers to two decimal places.) biomass households LPG households What is the simultaneous confidence level for the two intervals? (Round your answer to two decimal places.) % (b) Carry out a test of hypotheses at significance level 0.01 to decide whether true average PEF is lower for children in biomass households than it is for children in LPG households (the article included a P-value for this test). (Round your test statistic to two decimal places and your P- value to four decimal places.) State the relevant hypotheses. O Ho: Mbiomass - MLPG = 0 Ha: Ubiomass - MLPG < 0 Ho: Mbiomass - MLPG = 0 Ha: Mbiomass - MLPG + 0 O Ho: Ubiomass - MLPG = 0 Hai Mbiomass - MLPG SO Ho: Mbiomass - uLPG = 0 Ha: Mbiomass - MLPG > 0 O Ho: Mbiomass - MLPG = 0 Ha: Mbiomass - MLPG 20 Calculate the test statistic and p-value. (Round your test statistic to two decimal places and your p-value to three decimal places.) z = P-value =

Answer 1

Volationis Aliance en solid biomids fire fise Cooking and healing" Rézcrired information vigilan bu biontes have had Ioni borse hold ni= 455 no 151 Xi = 3.0 x = (1.46 (1= 1. (923 194 for the populatio Cocoak: @ Caecelaki a confidence interval at the 9.5 l. C.- cue have to oblained 954. of conifickose inkerial mean its) Elere, CE) Biomass - bocise hands is 95.1. of C. I = 814 Povl * O where d=1-GI 7x12= 70.005 1242 cla6 =1957 =1-0.95 x =0.05 120.05/2 2/2 =0.0051 From Eqr , we get 25.1. of C.1 = 3.00 (1.06 * 45 ) -3.0+ [1.964 0.00136+) = 3.21 0.08559 = (3.2 - 0.08559, 3.Q+ 0.08559)

95-1. of CIS P2.11a, 3. 085] 3.11, 3.224 (ii) LPG becase Howells i 964. 4. Iï t two 2066 1.964/16041 - 4.46 1 11.06.0.07051 = 4.46 (0.13820) =[21.496-0.1362061.665 +0.0820] = (4.021 , 4.598] < (41.30, (.59] Therefore, biomass bouse holds [3-4), 309) ] Loc bocuse bolds [ (1-3), L159} ] Caño cobat X the sinceltaneou_intervali- to to obtained simultaneatly confidence love for the vel is, interval is Here, Simultaneous confidence interval is = 95.4. *95:15 = 0.95*0.95 = 0.0005 = 0.0025*100 - 60.05°C) Therefore, Osinaltaneous interval is 0.90005 Cor) 20.05°6)

orty out the H651 ☺ Select hypothesis is hale to oblained the rulare allora Vin Dipothesis 1 and out che sole to oblained the real Here, Beli Bypothesis is Hol: le biensass - 91 LAC =0 and, alternative bypothesis He] : lebiomass- IILPG <o There fore, option D is correct answer LES Calculate test (Hatilla and p-valdis le have to obtained the test (statilstic and p-value is Here, its fest (statistia 1-62 SI² +62² D2 DI 2 CL904 7 757 755 -626 6-87904603 10 0.0829

- - 1519 [Z=-1549] and uplalice is pralce (t-test) -(-15.L] pralcel - 0.0001) Therefore, 7--15.19 pralce = 0.0001 lecce 420.01 we have to compared significane p-value and (fere, place << 0.0001 @ 0.01 wa rejected null nypothesis to at &=0.019 c hers Cars Race that the Beject to che data Cuggests that the free alberage PEF is lower for children in biomass house hold then it is for chieden in LPG bocuse holds