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    • ▾4th grade
      • ▸Place value of whole numbers
        • •Place value of multi-digit whole numbers
        • •Adding and subtracting multi-digit numbers
        • •Multiply and divide by 10
        • •Represent a number using base ten blocks, units, tens, and hundreds
        • •Convert between written forms of numbers
        • •Round whole numbers
        • •Estimating sums and differences by rounding
        • •Estimating products by rounding
      • ▸Multiplication and division
        • •Multiplying one-digit numbers by 10, 100, and 1000
        • •Multiplying one-digit numbers by multiples of 10, 100, and 1000
        • •Multiplying 10s
        • •Multiplication
        • •Quotients and remainders
        • •Pattern in the units digit of multiples
        • •Solve multiplication and division word problems
        • •Multi-step word problems
      • ▸Factors, multiples, and patterns
        • •Factors and multiples
        • •Divisibility tests
        • •Prime and composite numbers
        • •Number patterns
      • ▸Equivalent fractions and comparing fractions
        • •Equivalent fractions
        • •37 trick
        • •Compare fractions with unlike numerators, denominators, or both
      • ▾Fraction arithmetic
        • •Round fractions
        • •Add and subtract fractions with like denominators
        • •Add fractions with denominators of 10 or 100
        • •Multiply fractions by whole numbers
      • ▸Understand decimals
        • •Represent decimal numbers using base ten blocks
        • •Compare decimals to hundredths
      • ▸Geometry
        • •Intro to parallel and perpendicular lines
        • •Lines of symmetry
        • •Rotational symmetry
        • •Intro to angles
        • •Measuring and drawing angles
        • •Coterminal angles
        • •Naming angles
        • •Adjacent angles and the additive property of angles
      • ▸Units of measurement
        • •Converting larger units of volume to smaller ones
        • •Converting larger units of length to smaller ones
        • •Converting larger units of time to smaller ones
        • •Word problems involving measures
     › 4th grade › Fraction arithmetic

    Add fractions with denominators of 10 or 100

    Add fractions with unlike denominators when the denominator is 10 or 100. Once practiced, do the same mentally. For example, 3/10 + 2/100 = 32/100. This is similar to adding decimals without regrouping.

    Watch these Khan Academy videos:

    • Adding fractions (denominators 10 & 100) by Khan Academy
    • Adding fractions: 7/10+13/100

    Do these Khan Academy exercises:

    • Equivalent expressions with common denominators (denominators 10 & 100)
    • Add fractions (denominators 10 & 100)

    Next, give your students this challenge:

    2,4,6,8 by NRICH

    Conclude by leading this investigation:

    Complete the Quadrilateral
    by MathPickle

    4.NF.C.5: Express a fraction with denominator 10 as an equivalent fraction with denominator 100, and use this technique to add two fractions with respective denominators 10 and 100. For example, express 3/10 as 30/100, and add 3/10 + 4/100 = 34/100.