1st Grade Math Flashcards: Addition And Subtraction Fluency

What this deck covers

This deck focuses on Addition And Subtraction Fluency, giving you a quick way to review the definitions, rules, and examples that matter most for 1st Grade Math.

How to use these flashcards

Work through these flashcards in short sessions. Try to answer each prompt before flipping the card, then revisit any cards you miss until the explanation feels automatic.

Flashcard 1: What is $12-8$ if you know the related fact $8+4=12$?

Answer: $4$. Since $8+4=12$, the missing addend in $8+?=12$ is $4$.

Flashcard 2: What is the value of $11-7$ using the related addition fact $7+4=11$?

Answer: $4$. Since $7+4=11$, then $11-7=4$.

Flashcard 3: What is $14-6$ by decomposing to ten: $14-4-2$?

Answer: $8$. Subtract $4$ to reach $10$, then subtract remaining $2$.

Flashcard 4: What is $17-10$?

Answer: $7$. Subtract $10$ from teen numbers by removing the ten.

Flashcard 5: What is the sum $8+6$ if you make a ten first?

Answer: $14$. Break $8+6$ into $8+2+4$ to make $10+4$.

Flashcard 6: What is $10-6$?

Answer: $4$. Basic subtraction fact within $10$.

Flashcard 7: What is the difference $14-5$ by decomposing to reach $10$ first?

Answer: $9$. $14-4=10$, then $10-1=9$.

Flashcard 8: What strategy is shown by starting at $9$ and counting on $3$ more to find $9+3$?

Answer: Counting on. Start at the larger number and count up by the smaller.

Flashcard 9: What is the sum $8+6$ using the making-ten strategy?

Answer: $14$. $8+2=10$, then $10+4=14$.

Flashcard 10: What is $9-6$ if you know the related fact $6+3=9$?

Answer: $3$. Since $6+3=9$, the missing addend in $6+?=9$ is $3$.

Flashcard 11: What is the sum $7+8$ by making ten first?

Answer: $15$. $7+3=10$, then $10+5=15$.

Flashcard 12: What is the sum $6+7$ by using the easier sum $6+6+1$?

Answer: $13$. Rewrite as $6+6+1$ since doubles are easier to recall.

Flashcard 13: What is $12-5$ by decomposing to ten: $12-2-3$?

Answer: $7$. Subtract $2$ to reach $10$, then subtract remaining $3$.

Flashcard 14: What is the difference $16-7$ by decomposing to reach $10$ first?

Answer: $9$. $16-6=10$, then $10-1=9$.

Flashcard 15: What strategy is shown by rewriting $8+6$ as $8+2+4$ to make $10$ first?

Answer: Making ten. Breaks apart numbers to create $10$, then adds the rest.

Flashcard 16: What is the sum $3+8$ by counting on from $8$?

Answer: $11$. Start at $8$ and count: $9, 10, 11$.

Flashcard 17: What is $6+6$?

Answer: $12$. Doubles fact: $6$ added to itself.

Flashcard 18: What is the sum $4+9$ by counting on from $9$?

Answer: $13$. Start at $9$ and count: $10, 11, 12, 13$.

Flashcard 19: What is $8+4$?

Answer: $12$. Basic addition fact within $20$.

Flashcard 20: What is the difference $16-9$ by counting on from $9$ to $16$?

Answer: $7$. Count up from $9$: $10, 11, 12, 13, 14, 15, 16$ is $7$ steps.

Flashcard 21: What is the value of $15-6$ using the fact that $6+9=15$?

Answer: $9$. Since $6+9=15$, then $15-6=9$.

Flashcard 22: What is $9+5$ using making ten: $9+1+4$?

Answer: $14$. Take $1$ from $5$ to make $10$ with $9$, then add remaining $4$.

Flashcard 23: What is the sum $10+7$ within $20$?

Answer: $17$. Adding to $10$ is easy: just append the ones digit.

Flashcard 24: What is $11-3$ by decomposing to ten: $11-1-2$?

Answer: $8$. Subtract $1$ to reach $10$, then subtract remaining $2$.

Flashcard 25: What is $12-4$ if you know the related fact $8+4=12$?

Answer: $8$. Since $8+4=12$, the missing addend in $4+?=12$ is $8$.

Flashcard 26: What is $10-9$?

Answer: $1$. Basic subtraction fact within $10$.

Flashcard 27: What is the sum $6+7$ by using an easier equivalent sum such as $6+6+1$?

Answer: $13$. Rewrite as $6+6+1=12+1=13$.

Flashcard 28: What relationship helps you use $8+4=12$ to solve $12-8$ quickly?

Answer: Addition and subtraction are inverse operations. Addition and subtraction undo each other.

Flashcard 29: What is the difference $20-10$?

Answer: $10$. Subtracting $10$ from $20$ leaves $10$.

Flashcard 30: What is the difference $15-8$ by counting on from $8$ to $15$?

Answer: $7$. Count up from $8$: $9, 10, 11, 12, 13, 14, 15$ is $7$ steps.

Flashcard 31: What is $7+7$?

Answer: $14$. Doubles fact: $7$ added to itself.

Flashcard 32: What is the difference $13-4$ by decomposing to reach $10$ first?

Answer: $9$. $13-3=10$, then $10-1=9$.

Flashcard 33: What strategy is shown by rewriting $13-4$ as $13-3-1$ to reach $10$ first?

Answer: Decomposing to make ten. Breaks subtraction into steps that pass through $10$.

Flashcard 34: What is the difference $12-3$ by decomposing to reach $10$ first?

Answer: $9$. $12-2=10$, then $10-1=9$.

Flashcard 35: What is the value of $12-8$ using the fact that $8+4=12$?

Answer: $4$. Since $8+4=12$, then $12-8=4$.

Flashcard 36: What is $7+8$ using making ten: $7+3+5$?

Answer: $15$. Take $3$ from $8$ to make $10$ with $7$, then add remaining $5$.

Flashcard 37: What is $10-7$ if you know the related fact $7+3=10$?

Answer: $3$. Since $7+3=10$, the missing addend in $7+?=10$ is $3$.

Flashcard 38: What is the sum $9+9$ within $20$?

Answer: $18$. Double facts: $9+9=18$.

Flashcard 39: What is $13-4$ by decomposing to ten: $13-3-1$?

Answer: $9$. Subtract $3$ to reach $10$, then subtract remaining $1$.

Flashcard 40: What is the sum $9+5$ by making ten first?

Answer: $14$. $9+1=10$, then $10+4=14$.