Your teacher will give you a set of cards that show story problems, diagrams, number lines, and equations.
Match each story with a diagram, a number line, and an equation. Be ready to explain your reasoning.
Activity 2
Solve each problem. Use a number line or diagram if it helps.
Clare starts with 24 cubes and adds some more. She makes a train with 42 cubes. How many cubes does she add on?
Andre has 37 cubes. He adds 39 more to make the train longer. How many cubes does he use?
Mai adds 8 cubes to her train. Now it is 55 cubes long. How long was her train before she added cubes?
Student Section Summary
We solved all types of problems and represented them in different ways. We represented addition and subtraction on number lines. We made connections to equations and strategies. We added and subtracted within 100. We used diagrams, base-ten blocks, number lines, and equations to show our thinking and make sense of stories and situations. .
Standards Alignment
Building On
2.MD.6
Represent whole numbers as lengths from 0 on a number line diagram with equally spaced points corresponding to the numbers 0, 1, 2, …, and represent whole-number sums and differences within 100 on a number line diagram.
Use addition and subtraction within 100 to solve one- and two-step word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem.
Represent whole numbers as lengths from 0 on a number line diagram with equally spaced points corresponding to the numbers 0, 1, 2, …, and represent whole-number sums and differences within 100 on a number line diagram.
Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction.
Use addition and subtraction within 100 to solve one- and two-step word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem.
Represent whole numbers as lengths from 0 on a number line diagram with equally spaced points corresponding to the numbers 0, 1, 2, …, and represent whole-number sums and differences within 100 on a number line diagram.
Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction.
Use addition and subtraction within 100 to solve one- and two-step word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem.
