Chapter 4.2, Problem 9E

In the following exercises, find the exponential model as follows: If you do not have suitable technology, use the first and last data points to find a function. (See Examples 3 and 4.) If you have a graphing calculator or other suitable technology, use exponential regression to find a function. (See Example 4.)

Chinese Bank Assets The table shows the total assets (in trillion yuan) held in Chinese banks for the given years.

Year	2000	2005	2007	2009	2011	2013	2015
Assets	17	41	53	79	118	151	199

Find the exponential model for these data, where $t=0$ corresponds to the year 2000.

Assume that the model remains accurate, and predict the total assets in 2018 and 2021.

Use a graphing calculator (or trial and error) to determine the first full year in which the total assets exceed 450 trillion yuan.