2024 AMC 8 Problems/Problem 10

Problem

In January $1980$ the Mauna Loa Observatory recorded carbon dioxide (CO2) levels of $338$ ppm (parts per million). Over the years the average CO2 reading has increased by about $1.515$ ppm each year. What is the expected CO2 level in ppm in January $2030$ ? Round your answer to the nearest integer.

$\textbf{(A)}\ 24\qquad \textbf{(B)}\ 25\qquad \textbf{(C)}\ 26\qquad \textbf{(D)}\ 27\qquad \textbf{(E)}\ 28$

Solution 1

This is a time period of $50$ years, so we can expect the ppm to increase by $50*1.515=75.75~76$ . $76+338=\boxed{\textbf{(B)\ 414}}$ .

-ILoveMath31415926535

Solution 1

For each year that has passed, the ppm will increase by $50$ . In $2030$ , the CO2 would have increased by $50\cdot 1.515 \approx 76,$ so the total ppm of CO2 will be $76 + 338 = \boxed{\textbf{(B)\ 414}}.$