Lazada. The Map of Southeast Asian E-Commerce Q3 2019 report presented by Marketing in Asia shows that Lazada, an international e-commerce company headquartered in Singapore, has the highest number of monthly active users in Q3 2019 in Malaysia and Singapore.

Lazada.com is reported to have about 18.25 million and 7.80 million of monthly visitors in Malaysia and Singapore, respectively (https://marketinginasia.com/

wp-content/uploads/2019/12/The-Map-Of-E-commerce-

In-Singapore.pdf).

A sample of 3,528 e-commerce platform users were randomly selected from Malaysia, and it was found that 1,347 of the users were active users on Lazada.com. Another sample of 1,957 e-commerce platform users were randomly selected from Singapore, and it was determined that 779 of them were active users on Lazada.com.

a) Is there evidence that the percentage of active users on Lazada is different for the two countries?

b) Give a 90% confidence interval for the difference in proportions.