Chapter SH, Problem 8.7APP

To determine

To calculate: Percent change in the concentration of carbon dioxide over the past 40 years.

Answer to Problem 8.7APP

Percent change in the concentration of carbon dioxide over the past 40 years is approximately $\underset{\_}{18\%}$ .

Explanation of Solution

Given:

Average carbon dioxide concentration in 1970 = $325\text{ parts per million}$

Average carbon dioxide concentration in 1960 = $385\text{ parts per million}$

Formula used:

Percent change is given by,

  $\text{Percent change = }\frac{\text{New value}-\text{old value}}{\text{Old value}}\times 100$

Calculation:

Percent change is calculated as:

  $\begin{array}{l}\text{Percent change = }\frac{\text{New value}-\text{old value}}{\text{Old value}}\times 100\\ \text{ = }\frac{385-325}{325}\times 100\\ =\frac{60}{325}\times 100\\ \approx 18\%\end{array}$

Conclusion:

Percent change in the concentration of carbon dioxide over the past 40 years is approximately $\underset{\_}{18\%}$ .