One-to-One Correspondence

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One-to-One Correspondence · Kindergarten · Worksheet 1

1. Tommy has 5 toy cars. He lines them up in a row. How many toy cars does Tommy have? Answer: 5 Solution: 1. Read the problem carefully: "Tommy has 5 toy cars." 2. The problem states that Tommy lines them up in a row, but this doesn't change the number of toy cars he has.
   Full step-by-step solution

   Step-by-step solution: 1. Read the problem carefully: "Tommy has 5 toy cars." 2. The problem states that Tommy lines them up in a row, but this doesn't change the number of toy cars he has. Lining them up is just arranging them, not adding or removing any cars. 3. The question asks: "How many toy cars does Tommy have?" 4. From the first sentence, we know Tommy started with 5 toy cars. 5. Since no cars were added or removed, the number remains the same. 6. Therefore, Tommy has 5 toy cars. Final answer: 5

2. Matiu has 12 toy cars. He gives 1 toy car to each of his friends. How many friends get a toy car? Answer: 12 Solution: Matiu has 12 toy cars. Step 2: He gives 1 car to each friend. Step 3: This is a one-to-one match: 1 car for 1 friend.
   Full step-by-step solution

   Step 1: Matiu has 12 toy cars. Step 2: He gives 1 car to each friend. Step 3: This is a one-to-one match: 1 car for 1 friend. Step 4: The number of friends equals the number of cars. Step 5: 12 cars means 12 friends get a car. The answer is 12.

3. Each child at the birthday party needs one balloon. There are 8 children. How many balloons are needed? Answer: 8 Solution: Each child needs one balloon. There are 8 children. For one-to-one matching, the number of balloons needed equals the number of children.
   Full step-by-step solution

   Step 1: Each child needs one balloon. Step 2: There are 8 children. Step 3: For one-to-one matching, the number of balloons needed equals the number of children. Step 4: 8 children need 8 balloons. The answer is 8.

4. Mason has 7 toy cars. He wants to give one toy car to each of his friends. How many friends can get a toy car? Answer: 7 Solution: Count the toy cars: 1, 2, 3, 4, 5, 6, 7. There are 7 toy cars. Each friend gets exactly one toy car.
   Full step-by-step solution

   Step 1: Count the toy cars: 1, 2, 3, 4, 5, 6, 7. There are 7 toy cars. Step 2: Each friend gets exactly one toy car. Step 3: So the number of friends who can get a toy car is the same as the number of toy cars. Step 4: 7 toy cars means 7 friends can get one. The answer is 7.

5. Matiu has 15 toy cars. He gives 1 toy car to each of his friends. How many friends get a toy car? Answer: 15 Solution: Count the toy cars: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15. There are 15 toy cars. Step 2: Each friend gets exactly 1 toy car.
   Full step-by-step solution

   Step 1: Count the toy cars: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15. There are 15 toy cars. Step 2: Each friend gets exactly 1 toy car. Step 3: So the number of friends is the same as the number of toy cars. Step 4: 15 toy cars means 15 friends. The answer is 15.

6. Emma has 5 toy ducks. Her friend Liam gives her 4 more toy ducks. How many toy ducks does Emma have now? Answer: 9 Solution: Emma starts with 5 toy ducks Liam gives her 4 more toy ducks Add the ducks together: 5 + 4 5 + 4 = 9 Emma has 9 toy ducks now.
   Full step-by-step solution

   Step 1: Emma starts with 5 toy ducks Step 2: Liam gives her 4 more toy ducks Step 3: Add the ducks together: 5 + 4 Step 4: 5 + 4 = 9 Emma has 9 toy ducks now.

7. Matiu has 12 toy dinosaurs. Each dinosaur needs 1 toy tree to play under. How many toy trees does Matiu need? Answer: 12 Solution: Matiu has 12 toy dinosaurs. Each dinosaur needs 1 toy tree. Match each dinosaur to one tree: dinosaur 1 gets tree 1, dinosaur 2 gets tree 2, and so on up to dinosaur 12.
   Full step-by-step solution

   Step 1: Matiu has 12 toy dinosaurs. Step 2: Each dinosaur needs 1 toy tree. Step 3: Match each dinosaur to one tree: dinosaur 1 gets tree 1, dinosaur 2 gets tree 2, and so on up to dinosaur 12. Step 4: Counting all the trees gives 12 toy trees. The answer is 12.

8. 7 dogs each need 1 bone. How many bones? Answer: 7 Solution: There are 7 dogs. Step 2: Each dog needs 1 bone. Step 3: Count the dogs: 1, 2, 3, 4, 5, 6, 7.
   Full step-by-step solution

   Step 1: There are 7 dogs. Step 2: Each dog needs 1 bone. Step 3: Count the dogs: 1, 2, 3, 4, 5, 6, 7. Step 4: Since each dog gets exactly one bone, you need 7 bones. The answer is 7.

9. Olivia has 10 toy horses. Each horse needs 1 saddle. How many saddles does Olivia need? Answer: 10 Solution: Olivia has 10 toy horses. Step 2: Each horse needs exactly 1 saddle. Step 3: Match each horse to one saddle: the first horse gets 1 saddle, the second horse gets 1 saddle, and so on, until all 10 horses have a saddle.
   Full step-by-step solution

   Step 1: Olivia has 10 toy horses. Step 2: Each horse needs exactly 1 saddle. Step 3: Match each horse to one saddle: the first horse gets 1 saddle, the second horse gets 1 saddle, and so on, until all 10 horses have a saddle. Step 4: Count the saddles: 1 for each horse gives 10 saddles. The answer is 10.

10. Emma has 5 toy boats. Each boat needs 1 sailor. How many sailors does Emma need? Answer: 5 Solution: Emma has 5 toy boats. Step 2: Each boat needs 1 sailor. Step 3: Match each boat to one sailor: boat 1 gets sailor 1, boat 2 gets sailor 2, boat 3 gets sailor 3, boat 4 gets sailor 4, boat 5 gets sailor 5.
    Full step-by-step solution

    Step 1: Emma has 5 toy boats. Step 2: Each boat needs 1 sailor. Step 3: Match each boat to one sailor: boat 1 gets sailor 1, boat 2 gets sailor 2, boat 3 gets sailor 3, boat 4 gets sailor 4, boat 5 gets sailor 5. Step 4: Count the sailors: 1, 2, 3, 4, 5. The answer is 5.