Question

Translate the statement into a confidence interval. Approximate the level of confidence. In a survey of 1000 adults in a country, 78% said being able to speak the language is at the core of national identity. The survey's margin of error is +3.5%.

Answer 1

Given :

n = 1000

p = 0.78

E = 0.035

we know that Z 212 - E2X PC lap) (0.035)2 x 1000 0.78 C1-0.78) 2²212 7:1387 2012 = 7:1387 Za12 2.6718 o 2: 67

Area to the right of 2 - scone (267) is 0.0038 Therefoch 212: 0.0038 0038 X 2 0:0076 0.008 Now significance level, La 1- x 100 0·008 - 1 100 ta99.2% Level of confidence is gg.2 %