Hypothesis Testing

Parts (i) to (iii) are based the following information:

Bettina, the general manager for Cornwall Steakhouse, trained her service staff to suggest wine with their customers’ meals. Last month, 55% of customers ordered wine with their meal. A month following the training, she randomly selected 38 receipts. Twenty-six of them included wine sales. Is there evidence that the proportion of customers ordering wine with their meals had increased?

(ii) What is the test statistic?
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