### Calculating Population Growth

Pick a country of your choice that is experiencing population growth.(I picked Mexico City,Mexico;18,131,000 in 2007, r is 1.7% expected to double in 40 years (0.69/0.017=40.6) pop. growth rate 1.142%(2008 est)(www.indexmundi.com/mexic/population-growth-rate.html)-I don't know what to do here...find the most recent population co