options: Rewrite rational expressions.

Write expressions in equivalent forms to solve problems.

Gain familiarity with factors and multiples.

Generate and analyze patterns.

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

Use polynomial identities to solve problems.

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

Solve equations and inequalities in one variable.

Represent and analyze quantitative relationships between dependent and independent variables.

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

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

Represent and solve problems involving addition and subtraction.

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

Represent and solve problems involving multiplication and division.

Use properties of operations to generate equivalent expressions.

Use the four operations with whole numbers to solve problems.

Apply and extend previous understandings of arithmetic to algebraic expressions.

Analyze patterns and relationships.

Represent and solve equations and inequalities graphically.

Work with addition and subtraction equations.

Perform arithmetic operations on polynomials.

Solve systems of equations.

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

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

Add and subtract within 20.

Understand the relationship between zeros and factors of polynomials.

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

Work with radicals and integer exponents.

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

Multiply and divide within 100.

Create equations that describe numbers or relationships

Reason about and solve one-variable equations and inequalities.

Interpret the structure of expressions.

Write and interpret numerical expressions.
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: 30