I got a question 'Based on the Nielsen ratings, the local CBS affiliate claims its 11 p. newscast reaches 41% of the viewing audience in the area.

I got a question 'Based on the Nielsen ratings, the local CBS affiliate claims its 11 p.m. newscast reaches 41% of the viewing audience in the area. In a survey of 100 viewers, 36% indicated that they watch the late evening news on this local CBS station. What is the test statistic?  ' and the answer was -1.02. But I don't know how did that answer come