Question

What's the answer of the problem below?

Answer 1

2007 - Piper Gene Munster, the person responsible for a survey dedicated to Apple in which he “found” out an estimated number of iPhones that were sold, has come up with yet another interesting theory.

According to Munster and the past-week Apple announcement about 1 million iPhones sold, the calculations take to the conclusion that after the price cut, the sales are up by more than 100%. . .

By Munster’s reckoning, Apple and AT&T were selling an average of 9,000 iPhones a day before the price reduction, which would have put their quarterly sales at 594,000 as of September 5.
By the end of the quarter, he believes Apple will have sold a total of 1.28 million iPhones. What was the price elasticity of demand for iPhones in 2007 if the percentage change in price was 40%?

Answer 2

WELCOME TO OS
any ideas?