Grade: Grade 1 Subject: SAT/ACT Skills Unit: Mental Math Warmups Lesson: 6 of 6 SAT Domain: ProblemSolving+DataAnalysis ACT Section: Math

Mixed Set

Learn

Congratulations! You have learned addition, subtraction, question types, timed drills, and how to review mistakes. Now it is time to put it all together!

What is a Mixed Set?

A mixed set has different types of problems all mixed up together. You might see:

  • Addition problems (like 5 + 3)
  • Subtraction problems (like 9 - 4)
  • Fill in the blank (like ___ + 2 = 7)
  • Word problems
  • True or false questions

How to Solve a Mixed Set

  1. Read carefully: Look at each problem. Is it addition or subtraction?
  2. Identify the type: What kind of question is it?
  3. Solve step by step: Take your time on each one.
  4. Check your work: Does your answer make sense?

Remember: The + sign means add (put together). The - sign means subtract (take away). Always look at the sign before you solve!

Examples

Here are some mixed problems with solutions:

Example 1: Addition

4 + 7 = ?

Solution: Start at 4, count up 7: 5, 6, 7, 8, 9, 10, 11. Answer: 11

Example 2: Subtraction

12 - 4 = ?

Solution: Start at 12, count back 4: 11, 10, 9, 8. Answer: 8

Example 3: Fill in the Blank

___ - 3 = 5

Solution: Think: "What number minus 3 equals 5?" 5 + 3 = 8. Answer: 8

Example 4: Word Problem

Lily has 6 books. She gives 2 to her friend. How many books does Lily have now?

Solution: "Gives away" means subtract. 6 - 2 = 4. Answer: 4 books

Practice

Complete this mixed set. Try to use everything you have learned!

  1. 8 + 3 = ___

    Show Answer

    11

  2. 10 - 5 = ___

    Show Answer

    5

  3. ___ + 4 = 9

    Show Answer

    5 (because 5 + 4 = 9)

  4. Is 7 + 4 = 12 true or false?

    Show Answer

    FALSE (7 + 4 = 11, not 12)

  5. Ben has 9 grapes. He eats 3. How many grapes does Ben have left?

    Show Answer

    6 grapes (9 - 3 = 6)

  6. 5 + 6 = ___

    Show Answer

    11

  7. 11 - 7 = ___

    Show Answer

    4

  8. Which is more: 6 + 3 or 10 - 2?

    Show Answer

    6 + 3 (6 + 3 = 9 and 10 - 2 = 8, so 9 is more)

  9. ___ - 2 = 8

    Show Answer

    10 (because 10 - 2 = 8)

  10. Amy has 4 toy cars. Her dad gives her 5 more. How many toy cars does Amy have now?

    Show Answer

    9 toy cars (4 + 5 = 9)

  11. Is 12 - 6 = 6 true or false?

    Show Answer

    TRUE (12 - 6 = 6)

  12. 7 + 5 = ___

    Show Answer

    12

Great Job!

You have completed the Mental Math Warmups unit! Count how many you got right:

  • 10-12 correct: Amazing! You are a mental math master!
  • 7-9 correct: Excellent work! Keep practicing!
  • 4-6 correct: Good effort! Review the lessons you found tricky.
  • 0-3 correct: Do not give up! Go back through the unit and try again.

Check Your Understanding

Answer these questions about the whole unit:

  1. What is the difference between addition and subtraction?
  2. What should you do if you get stuck on a problem?
  3. Why is it important to check your work?
  4. What is one thing you learned in this unit that you want to remember?
Show Sample Answers
  1. Addition means putting numbers together to get more. Subtraction means taking away to get less.
  2. Skip it and come back, use your fingers to count, or ask for help.
  3. To make sure you did not make a mistake and to catch errors before moving on.
  4. Answers will vary! Maybe you learned to read the + and - signs carefully, or to use counting to check your work.

Next Steps

  • Celebrate finishing this unit!
  • Practice mental math every day - even just a few problems helps
  • Try the timed drill again to see if you have gotten faster
  • Move on to the next SAT/ACT Skills unit to keep building your skills

Unit Complete!

You have finished all 6 lessons in Mental Math Warmups. Great work building your math speed and accuracy!