Finding the Unknown Number (in Addition) — Let's Practice!
Basics on the topic Finding the Unknown Number (in Addition) — Let's Practice!
Let's practice finding the unknown number with Razzi!
Transcript Finding the Unknown Number (in Addition) — Let's Practice!
Razzi says get a piece of paper and pencil ready (...) Because today we're going to practice... Finding the unknown number (in addition). It's time to begin! Remember, you can use parts, whole, and addition to help find the missing number. If Mr. Squeaks started with seven bits of wood for his new project, and ended up with twelve, how many bits did he add? Remember to write an equation, and fill in the parts that you know. Then, count up from part one until you reach the whole. How many numbers did you count? Did you also count five? So, the missing number is five! Let's tackle the next problem! Mr. Squeaks now has started building using screws. If he started with eight screws and finished with eleven, how many screws did he add? Remember to write an equation, and fill in the parts that you know. Then, count up from part one until you reach the whole. How many numbers did you count? Did you also count three ? So, the missing number is three! Let's tackle the next problem! If Mr. Squeaks has a pile of ten seeds and ends with a pile of sixteen seeds, how many seeds did he add? Remember to write an equation, and fill in the parts that you know. Then, count up from part one until you reach the whole. How many numbers did you count? Did you also count six ? The missing number is six! Razzi had so much fun practicing with you today! See you next time!
Finding the Unknown Number (in Addition) — Let's Practice! exercise
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Show the correct equation.
HintsRemember, an equation looks like this: part + part = whole
Look at this example. Imani has 10 candies. He gets more, and now he has 14 candies. How many did he get?
The equation is: the part we know + the part we don't know = the whole we know.
10 + ? = 14
SolutionThe equation we would write is 4 + ? = 13. We know Imani had 4 toys. Then, they added more and end with 13. The whole is 13, and one part is 4: 4 + ? = 13.
To solve, Imani counts up from 4 (5, 6, 7, 8, 9, 10, 11, 12, 13) to find that they added 9 toys from the store.
4 + 9 = 13
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Select the appropriate numbers to complete the equations.
HintsRemember, to find the part we don't know, we count up from the part we do know until we reach the whole.
Look at this example. 7 + ? = 14.
We start at the part we know (7) and count up to the whole (14).
7, 8, 9, 10, 11, 12, 13, 14. The missing part is 7.
Solution7 + 3 = 10 (7, 8, 9, 10)
3 + 6 = 9 (3, 4, 5, 6, 7, 8, 9)
8 + 7 = 15 (8, 9, 10, 11, 12, 13, 14, 15)
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Fill in the missing part.
HintsCount up from the part you know until you reach the whole.
Look at this example: 8 + ? = 14.
We start at 8, and count up until we reach 14.
8, 9, 10, 11, 12, 13, 14. The missing part is 6.
8 + 6 = 14
Solution5 + 6 = 11
3 + 7 = 10
9 + 4 = 13
To find the missing numbers, we started at the part and counted up until we reached the whole.
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Create the equation and solve.
HintsRemember, to create an equation, use the numbers you know. We know Mr. Squeaks planted 8 flowers. What else do we know?
Look at the story. What is the whole? How many flowers did they plant together?
An equation looks like this: part + part = whole
To find the missing part, start at the part we know and count up to reach the whole.
SolutionImani planted 5 flowers.
The equation is: 8 + 5 = 13.
We count up from one part (8) to the whole (13) to solve for the missing part.
8, 9, 10, 11, 12, 13. The missing number is 5.
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Count up to find the missing part.
HintsMr. Squeaks started with 6 toys and finished with 10. Count up from 6 to find the missing part.
Part + part = whole
SolutionImani gave Mr. Squeaks 4 toys today!
Mr. Squeaks already had 6 toys, and Imani gave him more. Now he has 10 toys. The equation is: 6 + ? = 10.
To solve, start at 6, and count up until 10. 6, 7, 8, 9, 10. The missing part is 4.
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Finish the equation and solve.
HintsRemember, to create an equation, use the numbers you know. We know Imani planted 4 tomatoes. What else do we know?
Look at the story. What is the whole? How many tomatoes did they plant together?
An equation looks like this: part + part = whole
To find the missing part, start at the part we know (4) and count up to reach the whole (13).
SolutionMr. Squeaks planted 9 tomato plants!
The equation is: 4 + 9 = 13.
We count up from one part (4) to the whole (13) to find the missing part.
4, 5, 6, 7, 8, 9, 10, 11, 12, 13. The missing number is 9*
