## Chapter 4, Lesson 11

An atom of copper weighs about 1.06 x 10^{—22} grams. A penny minted in the United States before 1982 was pure copper and weighed about 3.1 grams.

Write a numerical expression that can be used to find the number of atoms of copper that are in one pre-1982 penny.

On a calculator, the power of 10 needed for a number in scientific notation is displayed as E followed by the power of 10. Use a calculator to verify that 1.06 x 10^{—22} is displayed as 1.06E^{—22}.

Now use a calculator to evaluate the numerical expression you wrote to find the number of atoms of copper that are in one pre-1982 penny. From the calculator display, write the result in scientific notation rounded to the nearest hundredth.