Online "daily deal" sites (e.g., Groupon) offer customers a voucher to purchase a product at discount prices. However, the number of voucher purchases must exceed a predetermined number before the deal becomes active. This key number is termed the "tipping point" in marketing. Characteristics of the tipping point were investigated in the Journal of Interactive Marketing (February 2016). A sample of 2,617 vouchers purchased from daily-deal sites in Korea had a mean tipping point of 112 sales with a standard deviation of 560 sales. The researchers want to estimate the true mean tipping point of all daily deal offerings in Korea with 95% confidence. Find and practically interpret this interval estimate.