# Lesson 15

Adding and Subtracting with Scientific Notation

### Lesson Narrative

Students add and subtract with numbers expressed in scientific notation, including problems where both decimal and scientific notation are used. Students must make sense and use quantitative reasoning when making comparisons, for example, when comparing whether 5 planets side by side are wider than the Sun (MP1, MP2).

### Learning Goals

Teacher Facing

• Generalize (orally and in writing) a process of adding and subtracting numbers in scientific notation and interpret results in context.

### Student Facing

• I can add and subtract numbers given in scientific notation.

### CCSS Standards

For example, the number 425,000,000 in scientific notation is $$4.25 \times 10^8$$. The number 0.0000000000783 in scientific notation is $$7.83 \times 10^{\text-11}$$.