If annual real GDP per capita growth in South Africa averages 1.8%, how long will it take the country to double its real GDP per capita? (please provide your answer to the nearest year, if required) If Ireland took 15 years to double its real GDP per capita, what was its average annual GDP per capita growth rate during this period? (Please give your answer to two decimal places, if required) If annual real GDP per capita growth in Tanzania averages 0.8% per year, how long will it take the country to quadruple its real GÖP per capita? (please provide your answer to the nearest year, if required) If China took 40 years to increase its real GDP per capita eight fold, what was its average economic growth during this period? (Please give your answer to two decimal places, if required)