17.24 Alex Perry is an Australian fashion designer and television presenter, known for his womenswear. To estimate the mean time (in hours) taken by a tailor to create a woman’s gown, which will be part of his new evening wear collection, he selected a random sample of 45 tailors from 243 tailors in Sydney. The sample standard deviation for tailoring a gown is 47.13 hours.

He requires a 90% confidence interval for the population mean time spent extended to 10 hours on each side of the sample point estimate. What is the additional number of samples Alex needs to achieve his objective?