This optional lesson offers additional practice working with exponential functions and rational inputs. Students use the context of radiocarbon dating and their understanding of half-life to estimate the ages of artifacts. Though the mathematics is not new, students need to apply what they have learned to solve problems that are less straightforward than they have seen in earlier lessons, which requires sense making and perseverance (MP1).

Technology isn’t required for this lesson, but there are opportunities for students to choose to use appropriate technology to solve problems. We recommend making technology available.