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2-90.

The Gross National Product (GNP) of the United States in 1960 was $1.665·10^{12}$ dollars. Until 1989 it increased at a rate of $3.17\%$ per year.
Use this information to answer each of the questions below.

1. What was the GNP in 1989?

$y=1.665·10^{12}(1.0317)^{29}$

Multiply the GNP in 1960 by $1.0317$ twenty-nine times.

The GNP in 1989 is $4.116·10^{12}$ dollars.

2. Write an equation to represent the GNP $t$ years after 1960, assuming that the rate of growth remained constant.

Remember that the GNP increases by $3.17\%$ each year.

$y=1.66(10^{12})(1.0317)^t$

3. Do you think the rate of growth really remains constant? Explain.

If you don’t know or you aren’t sure, try looking it up on the internet. Look for a graph. You could enter GNP USA into a search engine.