In an article in the journal of advertising, weinberger and spotts compare the use of humor in television ads in the united states and the united kingdom. they found that a substantially greater percentage of u. k. ads use humor. (a) suppose that a random sample of 387 television ads in the united kingdom reveals that 130 of these ads use humor. find a point estimate of and a 95 percent confidence interval for the proportion of all u. k. television ads that use humor.

(0.293, 0.387)

Step-by-step explanation:

Given : Sample size : n=387  ;

Number of ads use humor=130

The the sample proportion for television ads use humor :

Significance level :

Critical value =

The confidence interval for population proportion is given by :_

i.e.  

Hence, the 95 percent confidence interval for the proportion of all U.K. television ads that use humor = (0.293, 0.387)

it's equivalent, so we can say that its equal.

let's call the denominator x and the numerador is 18 less then denominator, x - 18.

multiply

2.x = 5.(x - 18)

2x = 5x - 90

90 = 5x - 2x

90 = 3x

x = 90/3

x = 30

so: