Common Core: 1st Grade Math : Find the Missing Number in Addition and Subtraction Equations: CCSS.MATH.CONTENT.1.OA.D.8

Study concepts, example questions & explanations for Common Core: 1st Grade Math

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Example Questions

Example Question #1 : Find The Missing Number In Addition And Subtraction Equations: Ccss.Math.Content.1.Oa.D.8

Fill in the blank. 

\(\displaystyle 1+\)__________\(\displaystyle = 5\)

Possible Answers:

\(\displaystyle 1\)

\(\displaystyle 2\)

\(\displaystyle 0\)

\(\displaystyle 4\)

\(\displaystyle 3\)

Correct answer:

\(\displaystyle 4\)

Explanation:

To find the missing piece of an addition problem, you can take the biggest number minus the smallest number. \(\displaystyle 5-1=4\), which means \(\displaystyle 1+4=5\).

Example Question #2 : Find The Missing Number In Addition And Subtraction Equations: Ccss.Math.Content.1.Oa.D.8

Fill in the blank. 

\(\displaystyle 2+\)__________\(\displaystyle =20\) 

Possible Answers:

\(\displaystyle 15\)

\(\displaystyle 19\)

\(\displaystyle 16\)

\(\displaystyle 17\)

\(\displaystyle 18\)

Correct answer:

\(\displaystyle 18\)

Explanation:

To find the missing piece of an addition problem, you can take the biggest number minus the smallest number. \(\displaystyle 20-2=18\), which means \(\displaystyle 2+18=20\).

Example Question #3 : Find The Missing Number In Addition And Subtraction Equations: Ccss.Math.Content.1.Oa.D.8

Fill in the blank. 

\(\displaystyle 3+\)__________\(\displaystyle =19\) 

Possible Answers:

\(\displaystyle 15\)

\(\displaystyle 18\)

\(\displaystyle 17\)

\(\displaystyle 14\)

\(\displaystyle 16\)

Correct answer:

\(\displaystyle 16\)

Explanation:

To find the missing piece of an addition problem, you can take the biggest number minus the smallest number. \(\displaystyle 19-3=16\), which means \(\displaystyle 3+16=19\).

Example Question #4 : Find The Missing Number In Addition And Subtraction Equations: Ccss.Math.Content.1.Oa.D.8

Fill in the blank.

\(\displaystyle 5+\)__________\(\displaystyle =9\) 

Possible Answers:

\(\displaystyle 1\)

\(\displaystyle 2\)

\(\displaystyle 4\)

\(\displaystyle 5\)

\(\displaystyle 3\)

Correct answer:

\(\displaystyle 4\)

Explanation:

To find the missing piece of an addition problem, you can take the biggest number minus the smallest number. \(\displaystyle 9-5=4\), which means \(\displaystyle 5+4=9\).

Example Question #394 : How To Add

Fill in the blank. 

\(\displaystyle 7+\)__________\(\displaystyle =19\)

Possible Answers:

\(\displaystyle 14\)

\(\displaystyle 15\)

\(\displaystyle 13\)

\(\displaystyle 16\)

\(\displaystyle 12\)

Correct answer:

\(\displaystyle 12\)

Explanation:

To find the missing piece of an addition problem, you can take the biggest number minus the smallest number. \(\displaystyle 19-7=12\), which means \(\displaystyle 7+12=19\).

Example Question #1 : Find The Missing Number In Addition And Subtraction Equations: Ccss.Math.Content.1.Oa.D.8

Fill in the blank. 

\(\displaystyle 10+\)__________\(\displaystyle =16\) 

Possible Answers:

\(\displaystyle 7\)

\(\displaystyle 8\)

\(\displaystyle 9\)

\(\displaystyle 6\)

\(\displaystyle 5\)

Correct answer:

\(\displaystyle 6\)

Explanation:

To find the missing piece of an addition problem, you can take the biggest number minus the smallest number. \(\displaystyle 16-10=6\), which means \(\displaystyle 10+6=16\).

Example Question #3 : Find The Missing Number In Addition And Subtraction Equations: Ccss.Math.Content.1.Oa.D.8

Fill in the blank. 

\(\displaystyle 12+\)__________\(\displaystyle =15\)

Possible Answers:

\(\displaystyle 3\)

\(\displaystyle 2\)

\(\displaystyle 5\)

\(\displaystyle 6\)

\(\displaystyle 4\)

Correct answer:

\(\displaystyle 3\)

Explanation:

To find the missing piece of an addition problem, you can take the biggest number minus the smallest number. \(\displaystyle 15-12=3\), which means \(\displaystyle 12+3=15\).

Example Question #3 : Find The Missing Number In Addition And Subtraction Equations: Ccss.Math.Content.1.Oa.D.8

Fill in the blank. 

\(\displaystyle 13+\)__________\(\displaystyle =20\) 

Possible Answers:

\(\displaystyle 7\)

\(\displaystyle 8\)

\(\displaystyle 9\)

\(\displaystyle 10\)

\(\displaystyle 11\)

Correct answer:

\(\displaystyle 7\)

Explanation:

To find the missing piece of an addition problem, you can take the biggest number minus the smallest number. \(\displaystyle 20-13=7\), which means \(\displaystyle 13+7=20\).

Example Question #1464 : Numbers And Operations

Fill in the blank. 

\(\displaystyle 15+\)__________\(\displaystyle =16\) 

Possible Answers:

\(\displaystyle 4\)

\(\displaystyle 0\)

\(\displaystyle 3\)

\(\displaystyle 2\)

\(\displaystyle 1\)

Correct answer:

\(\displaystyle 1\)

Explanation:

To find the missing piece of an addition problem, you can take the biggest number minus the smallest number. \(\displaystyle 16-15=1\), which means \(\displaystyle 15+1=16\).

Example Question #8 : Find The Missing Number In Addition And Subtraction Equations: Ccss.Math.Content.1.Oa.D.8

Fill in the blank. 

\(\displaystyle 17+\)__________\(\displaystyle =19\) 

Possible Answers:

\(\displaystyle 5\)

\(\displaystyle 3\)

\(\displaystyle 1\)

\(\displaystyle 4\)

\(\displaystyle 2\)

Correct answer:

\(\displaystyle 2\)

Explanation:

To find the missing piece of an addition problem, you can take the biggest number minus the smallest number. \(\displaystyle 19-17=2\), which means \(\displaystyle 17+2=19\).

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