Understand Fraction Addition and Subtraction - 4th Grade Math
Card 1 of 20
Find the missing numerator: $\frac{\square}{8}+\frac{3}{8}=\frac{7}{8}$.
Find the missing numerator: $\frac{\square}{8}+\frac{3}{8}=\frac{7}{8}$.
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$4$. Need $4$ eighths since $4+3=7$.
$4$. Need $4$ eighths since $4+3=7$.
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Find and correct the error: $\frac{2}{9}+\frac{5}{9}=\frac{7}{18}$.
Find and correct the error: $\frac{2}{9}+\frac{5}{9}=\frac{7}{18}$.
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Correct: $\frac{2}{9}+\frac{5}{9}=\frac{7}{9}$. Keep denominator $9$; don't add denominators.
Correct: $\frac{2}{9}+\frac{5}{9}=\frac{7}{9}$. Keep denominator $9$; don't add denominators.
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What is the sum shown by joining parts: $\frac{1}{3}+\frac{1}{3}+\frac{1}{3}$?
What is the sum shown by joining parts: $\frac{1}{3}+\frac{1}{3}+\frac{1}{3}$?
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$\frac{3}{3}$. Three thirds make one whole: $\frac{3}{3}=1$.
$\frac{3}{3}$. Three thirds make one whole: $\frac{3}{3}=1$.
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Which option equals $\frac{5}{6}-\frac{1}{6}$: $\frac{4}{6}$ or $\frac{5}{12}$?
Which option equals $\frac{5}{6}-\frac{1}{6}$: $\frac{4}{6}$ or $\frac{5}{12}$?
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$\frac{4}{6}$. Subtract only numerators $5-1=4$, not denominators.
$\frac{4}{6}$. Subtract only numerators $5-1=4$, not denominators.
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Identify the correct result: $\frac{11}{12}-\frac{5}{12}=?$
Identify the correct result: $\frac{11}{12}-\frac{5}{12}=?$
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$\frac{6}{12}$. Subtract numerators: $11-5=6$, keep denominator $12$.
$\frac{6}{12}$. Subtract numerators: $11-5=6$, keep denominator $12$.
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Identify the correct result: $\frac{4}{7}+\frac{2}{7}=?$
Identify the correct result: $\frac{4}{7}+\frac{2}{7}=?$
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$\frac{6}{7}$. Add numerators: $4+2=6$, keep denominator $7$.
$\frac{6}{7}$. Add numerators: $4+2=6$, keep denominator $7$.
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What is the sum $\frac{5}{6}+\frac{1}{6}$?
What is the sum $\frac{5}{6}+\frac{1}{6}$?
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$\frac{6}{6}$. Add numerators: $5+1=6$, keep denominator $6$.
$\frac{6}{6}$. Add numerators: $5+1=6$, keep denominator $6$.
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What is the difference $\frac{7}{10}-\frac{3}{10}$?
What is the difference $\frac{7}{10}-\frac{3}{10}$?
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$\frac{4}{10}$. Subtract numerators: $7-3=4$, keep denominator $10$.
$\frac{4}{10}$. Subtract numerators: $7-3=4$, keep denominator $10$.
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What is the sum $\frac{3}{8}+\frac{2}{8}$?
What is the sum $\frac{3}{8}+\frac{2}{8}$?
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$\frac{5}{8}$. Add numerators: $3+2=5$, keep denominator $8$.
$\frac{5}{8}$. Add numerators: $3+2=5$, keep denominator $8$.
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What changes when you add fractions with like denominators, for example $\frac{3}{8}+\frac{2}{8}$?
What changes when you add fractions with like denominators, for example $\frac{3}{8}+\frac{2}{8}$?
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The numerator becomes the sum of the numerators. Add the number of pieces (numerators) when denominators match.
The numerator becomes the sum of the numerators. Add the number of pieces (numerators) when denominators match.
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What stays the same when you add fractions with like denominators, for example $\frac{3}{8}+\frac{2}{8}$?
What stays the same when you add fractions with like denominators, for example $\frac{3}{8}+\frac{2}{8}$?
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The denominator stays the same. The size of each piece (denominator) doesn't change when combining.
The denominator stays the same. The size of each piece (denominator) doesn't change when combining.
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What must be true about the whole when you add or subtract fractions in Grade $4$?
What must be true about the whole when you add or subtract fractions in Grade $4$?
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The fractions must refer to the same whole. Can't combine fractions from different-sized wholes (e.g., half a pizza vs. half a cookie).
The fractions must refer to the same whole. Can't combine fractions from different-sized wholes (e.g., half a pizza vs. half a cookie).
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What does it mean to subtract fractions with the same denominator, such as $\frac{a}{b}-\frac{c}{b}$?
What does it mean to subtract fractions with the same denominator, such as $\frac{a}{b}-\frac{c}{b}$?
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Separate parts of the same whole; subtract numerators, keep $b$. Like denominators mean removing pieces from the same-sized whole.
Separate parts of the same whole; subtract numerators, keep $b$. Like denominators mean removing pieces from the same-sized whole.
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What does it mean to add fractions with the same denominator, such as $\frac{a}{b}+\frac{c}{b}$?
What does it mean to add fractions with the same denominator, such as $\frac{a}{b}+\frac{c}{b}$?
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Join parts of the same whole; add numerators, keep $b$. When denominators match, fractions share the same-sized pieces.
Join parts of the same whole; add numerators, keep $b$. When denominators match, fractions share the same-sized pieces.
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Which option equals $\frac{1}{4}+\frac{2}{4}$: $\frac{3}{4}$ or $\frac{3}{8}$?
Which option equals $\frac{1}{4}+\frac{2}{4}$: $\frac{3}{4}$ or $\frac{3}{8}$?
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$\frac{3}{4}$. Add numerators $1+2=3$, not denominators.
$\frac{3}{4}$. Add numerators $1+2=3$, not denominators.
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Find the missing numerator: $\frac{9}{10}-\frac{\square}{10}=\frac{2}{10}$.
Find the missing numerator: $\frac{9}{10}-\frac{\square}{10}=\frac{2}{10}$.
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$7$. Subtract $7$ tenths since $9-7=2$.
$7$. Subtract $7$ tenths since $9-7=2$.
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What fraction completes the equation $\frac{8}{9}-\square=\frac{5}{9}$?
What fraction completes the equation $\frac{8}{9}-\square=\frac{5}{9}$?
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$\frac{3}{9}$. Subtract $3$ ninths since $8-3=5$.
$\frac{3}{9}$. Subtract $3$ ninths since $8-3=5$.
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What fraction completes the equation $\frac{2}{5}+\square=\frac{4}{5}$?
What fraction completes the equation $\frac{2}{5}+\square=\frac{4}{5}$?
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$\frac{2}{5}$. Need $2$ more fifths since $2+2=4$.
$\frac{2}{5}$. Need $2$ more fifths since $2+2=4$.
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Which operation matches the action: joining parts of the same whole, addition or subtraction?
Which operation matches the action: joining parts of the same whole, addition or subtraction?
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Addition (joining parts). Combining parts together increases the total amount.
Addition (joining parts). Combining parts together increases the total amount.
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What does the numerator tell you in $\frac{a}{b}$ when joining or separating fractional parts?
What does the numerator tell you in $\frac{a}{b}$ when joining or separating fractional parts?
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The numerator $a$ tells how many equal parts are taken. It counts how many of those equal-sized parts you have.
The numerator $a$ tells how many equal parts are taken. It counts how many of those equal-sized parts you have.
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