To find the average number of helium atoms per cubic centimeter, you can divide the total number of helium atoms by the total volume in cubic centimeters.
Given:
- Total helium atoms = 60,000,000,000 (or 60 billion)
- Volume = 30,000 cubic centimeters
The calculation is:
\[ \text{Average number of helium atoms per cubic centimeter} = \frac{\text{Total helium atoms}}{\text{Volume (cm}^3\text{)}} \]
\[ = \frac{60,000,000,000}{30,000} \]
Now, performing the division:
\[ = 2,000,000 \]
Therefore, the average number of helium atoms per cubic centimeter is 2,000,000.