  # Kentucky - Grade 1 - Math - Operations and Algebraic Thinking - Adding and Subtracting within 20 - KY.1.OA.4,5,6

### Description

KY1.OA.4 Understand subtraction as an unknown-addend problem. KY.1.OA.5 Relate counting to addition and subtraction. KY.1.OA.6 Add and subtract within 20. a.Fluently add and subtract within 10. b.Add and subtract within 20, demonstrating fluency for additionand subtraction within 10. Use strategies such as counting on;making 10; decomposing a number leading to a 10; using therelationship between addition and subtraction; treating equivalent but easier or known sums.

• State - Kentucky
• Standard ID - KY.1.OA.4,5,6
• Subjects - Math Common Core

### Keywords

• Math
• Operations and Algebraic Thinking

## More Kentucky Topics Understand the two-digits of a two-digit number represent amounts of tens and ones. Understand the following as special cases: a. 10 can be thought of as a bundle of ten ones — called a “ten.” b. The numbers from 11 to 19 are composed of a ten and one, two, three, four, five, six, seven, eight or nine ones. c. The numbers 10, 20, 30, 40, 50, 60, 70, 80, 90 refer to one, two, three, four, five, six, seven, eight or nine tens (and 0 ones). Use addition and subtraction within 20 to solve word problems involving situations of adding to, taking from, putting together, taking apart and comparing, with unknowns in all positions. Apply properties of operations as strategies to add and subtract. Given a two-digit number, mentally find 10 more or 10 less than the number, without having to count; explain the reasoning used. Distinguish between defining attributes versus non-defining attributes; build and draw shapes to possess defining attributes.

## Here is the skill that Kentucky requires you to master

• State Test K-PREP
• State Standards Kentucky Core Academic Standards
• Subject Math
• Topic Name Adding and Subtracting within 20
• Standard ID KY.1.OA.4,5,6
• Description
KY1.OA.4 Understand subtraction as an unknown-addend problem. KY.1.OA.5 Relate counting to addition and subtraction. KY.1.OA.6 Add and subtract within 20. a.Fluently add and subtract within 10. b.Add and subtract within 20, demonstrating fluency for additionand subtraction within 10. Use strategies such as counting on;making 10; decomposing a number leading to a 10; using therelationship between addition and subtraction; treating equivalent but easier or known sums.  