# Common Core Alignment

Wondering how Riddle Books aligns with the Common Core Standards? Check out the table below. See examples of each problem type by clicking the links in the problem type column.

CCSS | Explanation | Problem Type |

K.OA.2 | Solve addition and subtraction word problems, and add and subtract within 10, e.g., by using objects or drawings to represent the problem. | 1 – Part-Whole Addition/Subtraction 2 – Comparison Addition/Subtraction |

1.OA.1 | Use addition and subtraction within 2 0 to solve word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions, e.g., by using objects, drawings, and equations with a symbol for the unknown number to represent the problem. | 1 – Part-Whole Addition/Subtraction 2 – Comparison Addition/Subtraction |

1.OA.2 | Solve word problems that call for addition of three whole numbers whose sum is less than or equal to 20, e.g., by using objects, drawings, and equations with a symbol for the unknown number to represent the problem. | 1 – Part-Whole Addition/Subtraction 2 – Comparison Addition/Subtraction |

2.OA.1 | 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. | 5 – Two Step (mixed operations) |

3.OA.3 | Use multiplication and division within 100 to solve word problems in situations involving equal groups, arrays, and measurement quantities, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem. | 1 – Part-Whole Addition/Subtraction 2 – Comparison Addition/Subtraction 3 – Part-Whole Multiplication/Division 4 – Comparison Multiplication/Division |

3.OA.8 | Solve two-step word problems using the four operations. Represent these problems using equations with a letter standing for the unknown quantity. Assess the reasonableness of answers using mental computation and estimation strategies including rounding. | 1 – Part-Whole Addition/Subtraction 2 – Comparison Addition/Subtraction 5 – Two Step (mixed operations) |

4.OA.2 | Multiply or divide to solve word problems involving multiplicative comparison, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem, distinguishing multiplicative comparison from additive comparison. | 3 – Part-Whole Multiplication/Division 4 – Comparison Multiplication/Division |

4.OA.3 | Solve multistep word problems posed with whole numbers and having whole-number answers using the four operations, including problems in which remainders must be interpreted. Represent these problems using equations with a letter standing for the unknown quantity. Assess the reasonableness of answers using mental computation and estimation strategies including rounding. | 3 – Part-Whole Multiplication/Division 4 – Comparison Multiplication/Division 5 – Two Step (mixed operations) |

4.NF.3 | Understand a fraction a/b with a > 1 as a sum of fractions 1/b. d. Solve word problems involving addition and subtraction of fractions referring to the same whole and having like denominators, e.g., by using visual fraction models and equations to represent the problem. | 6 – Part-Whole Fractions 7 – Comparison Fractions |

4.NF.4 | Apply and extend previous understandings of multiplication to multiply a fraction by a whole number. | 6 – Part-Whole Fractions 7 – Comparison Fractions |

5.NF.2 | Solve word problems involving addition and subtraction of fractions referring to the same whole, including cases of unlike denominators, e.g., by using visual fraction models or equations to represent the problem. Use benchmark fractions and number sense of fractions to estimate mentally and assess the reasonableness of answers. For example, recognize an incorrect result 2/5 + 1/2 = 3/7, by observing that 3/7 < 1/2. | 6 – Part-Whole Fractions 7 – Comparison Fractions |

5.NF.3 | Interpret a fraction as division of the numerator by the denominator (a/b = a ÷ b). Solve word problems involving division of whole numbers leading to answers in the form of fractions or mixed numbers, e.g., by using visual fraction models or equations to represent the problem. | 6 – Part-Whole Fractions 7 – Comparison Fractions |

5.NF.6 | Solve real world problems involving multiplication of fractions and mixed numbers, e.g., by using visual fraction models or equations to represent the problem. | 6 – Part-Whole Fractions 7 – Comparison Fractions |

5.NF.7 | Apply and extend previous understandings of division to divide unit fractions by whole numbers and whole numbers by unit fractions. | 6 – Part-Whole Fractions 7 – Comparison Fractions |

6.RP.3 | Use ratio and rate reasoning to solve real-world and mathematical problems, e.g., by reasoning about tables of equivalent ratios, tape diagrams, double number line diagrams, or equations. | All build toward knowledge of these skills |

6.NS.1 | Interpret and compute quotients of fractions, and solve word problems involving division of fractions by fractions, e.g., by using visual fraction models and equations to represent the problem. | All build toward knowledge of these skills |

6.EE.6 | Use variables to represent numbers and write expressions when solving a real-world or mathematical problem; understand that a variable can represent an unknown number, or, depending on the purpose at hand, any number in a specified set. | All build toward knowledge of these skills |

6.EE.7 | Solve real-world and mathematical problems by writing and solving equations of the form x + p = q and px = q for cases in which p, q and x are all nonnegative rational numbers. | All build toward knowledge of these skills |

6.EE.8 | Write an inequality of the form x > c or x < c to represent a constraint or condition in a real-world or mathematical problem. Recognize that inequalities of the form x > c or x < c have infinitely many solutions; represent solutions of such inequalities on number line diagrams. | All build toward knowledge of these skills |

7.RP.3 | Use proportional relationships to solve multistep ratio and percent problems. | All build toward knowledge of these skills |

7.NS.A.3 | Solve real-world and mathematical problems involving the four operations with rational numbers. | All build toward knowledge of these skills |

7.EE.3 | Solve multi-step real-life and mathematical problems posed with positive and negative rational numbers in any form (whole numbers, fractions, and decimals), using tools strategically. Apply properties of operations to calculate with numbers in any form; convert between forms as appropriate; and assess the reasonableness of answers using mental computation and estimation strategies. | All build toward knowledge of these skills |

7.EE.4 | Use variables to represent quantities in a real-world or mathematical problem, and construct simple equations and inequalities to solve problems by reasoning about the quantities. | All build toward knowledge of these skills |