20.

In 2021, 70% of Gnagovian households had an internet connection. A sample of 80 households taken in 2022, showed that 75% had an internet connection. We are interested in determining whether or not there has been a significant increase in the percentage of the Gnagovian households that have internet connections. The null hypothesis is to be tested at 95% confidence.

The test statistic is

(round the final answer to two decimal places, e.g. 2.57)