Question

1. In a sample of 300 students, 204 said they own a tablet and a smart phone. Compute a 90% confidence interval for the true percent of students who own a tablet and a smartphone. Write your answer as a complete sentence.

Answer 1

colution Civen the information Let 0 = 300 - NO- of students XDumber of students have con X = 204 smartphone sample proportion of percentage of _student bave olon tablet: 20 smarphone - x - 20450-68 - population peacentage of student have blon tablet aq smartphones ca confidence level 90% cogo the formula for lo confidence interval for p is Té etz CALE) (P < +E) E = 2X12 * v pesme) To find Z412, de level of significance - 1-C g= 1-0-90 = 0-10 = 0.05 El 1-005-0.95 see in the e-table for what values of z, the area is 0.95. so for z=1.96 the area is 0.95 ..? 2012- Zoos- 1.96 -- (Foom z table) E 74606861-0fps 300 E - 196*10.0006253

E-0.05 I D-E - 0-68-0-05 -0.63 E = 0.68 toros = 0.73 ... The go% confidence interval for the true Hercent of students who have own tablet smoote hone (10.631 < p <10:737)