options: Know that there are numbers that are not rational, and approximate them by rational numbers.

Use properties of rational and irrational numbers.

Apply and extend previous understandings of operations with fractions to add, subtract, multiply, and divide rational numbers.

Use complex numbers in polynomial identities and equations.

Perform operations on vectors.

Apply and extend previous understandings of multiplication and division to divide fractions by fractions.

Extend the properties of exponents to rational exponents.

Compute fluently with multi-digit numbers and find common factors and multiples.

Reason quantitatively and use units to solve problems.

Perform arithmetic operations with complex numbers.

Represent complex numbers and their operations on the complex plane.

Apply and extend previous understandings of numbers to the system of rational numbers.

Perform operations on matrices and use matrices in applications.

Represent and model with vector quantities.
problem_activity: Task
Nina was finding multiples of 6. She said,
18 and 42 are both multiples of 6, and when I add them, I also get a multiple of 6: $$18+42 = 60.$$
Explain to Nina why adding two multiples of 6 will always result in another multiple of 6.


correct_option_index: 7