options: Solve equations and inequalities in one variable.

Work with addition and subtraction equations.

Work with equal groups of objects to gain foundations for multiplication.

Represent and analyze quantitative relationships between dependent and independent variables.

Analyze and solve linear equations and pairs of simultaneous linear equations.

Understand the connections between proportional relationships, lines, and linear equations.

Understand properties of multiplication and the relationship between multiplication and division.

Write and interpret numerical expressions.

Use the four operations with whole numbers to solve problems.

Analyze patterns and relationships.

Rewrite rational expressions.

Solve problems involving the four operations, and identify and explain patterns in arithmetic.

Understand addition as putting together and adding to, and understand subtraction as taking apart and taking from.

Represent and solve problems involving multiplication and division.

Gain familiarity with factors and multiples.

Multiply and divide within 100.

Use properties of operations to generate equivalent expressions.

Interpret the structure of expressions.

Understand the relationship between zeros and factors of polynomials.

Understand and apply properties of operations and the relationship between addition and subtraction.

Solve systems of equations.

Create equations that describe numbers or relationships

Understand solving equations as a process of reasoning and explain the reasoning.

Represent and solve problems involving addition and subtraction.

Generate and analyze patterns.

Reason about and solve one-variable equations and inequalities.

Write expressions in equivalent forms to solve problems.

Solve real-life and mathematical problems using numerical and algebraic expressions and equations.

Apply and extend previous understandings of arithmetic to algebraic expressions.

Add and subtract within 20.

Work with radicals and integer exponents.

Represent and solve equations and inequalities graphically.

Use polynomial identities to solve problems.

Perform arithmetic operations on polynomials.
problem_activity: Task
It takes Clea 60 seconds to walk down an escalator when it is not operating, and only 24 seconds to walk down the escalator when it is operating. How many seconds does it take Clea to ride down the operating escalator when she just stands on it?


correct_option_index: 21