A airline company provides an cheaper ticket that does not include checked in luggage. Customers can however check in their luggage for an additional cost. To manage fuel load in the most profitable way, the airline company wants to know whether the proportion of customers who pay for checked in luggage is different from 0.42. A sample of 58 customers was selected and it was found that 21 paid for checked in luggage. Compute the test statistic of an appropriate hypothesis test. Provide your answer to two decimal places.

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