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Overview
Grade 3 Math
Number
1. Describe and apply mental mathematics strategies for adding two 2-digit numerals
1.5 Adding with Doubles Up to 1000
Adding with Doubles Up to 1000
Learn the doubling strategy for adding numbers up to 1000 by scaling basic doubles facts like 6 plus 6 into hundreds and tens.
What You'll Learn
Recognize a doubles fact as any sum where both addends are equal, such as \( 6 + 6 = 12 \)
Scale a known doubles fact by place value, so \( 4 + 4 = 8 \) leads to \( 400 + 400 = 800 \)
Split a larger number into hundreds, tens, and ones before doubling each part separately
Apply the pattern \( 10 \times (a+a) \) to extend small doubles facts to tens and hundreds
Combine partial doubles sums back together to find the total, such as \( 600 + 100 = 700 \)
Check answers by comparing a doubled sum to the original number multiplied by two
What You'll Practice
1
Adding exact doubles like 250 + 250 or 400 + 400
2
Rewriting near doubles problems as doubles plus or minus one
3
Filling in missing addends in doubles equations
Why This Matters
Mastering doubles and near doubles gives you a powerful mental math strategy that makes addition faster and easier. This skill builds number sense and helps you solve everyday problems like calculating costs, measuring ingredients, or estimating quantities without a calculator.
This Unit Includes
4 Video lessons
Practice exercises
Learning resources
Skills
Doubles
Near Doubles
Mental Math
Addition
Number Sense
Fact Fluency
NS Curriculum Aligned