Introduction to Sequences

Hello, everyone! Today we are going to learn about sequences. A sequence is a list of numbers that follow a certain pattern. Our job is to complete the sequence by finding the missing numbers.

What is a Sequence?

A sequence can be numbers that go up or down. For example, if I say the numbers 1, 2, 3, what comes next? That’s right! The next number is 4. You are following a counting pattern!

Key Rules for Completing Sequences

  1. Counting Up: When numbers are going up, just keep adding 1.
    • Example: 1, 2, 3, __, __ (Answer: 4, 5)
  2. Counting Down: When numbers are going down, keep taking away 1.
    • Example: 5, 4, 3, __, __ (Answer: 2, 1)
  3. Skip Counting: Sometimes we count in 2s, 5s, or 10s.
    • Example (2s): 2, 4, 6, __, __ (Answer: 8, 10)

Tips and Tricks

  • Look for the pattern. Is it counting by 1, 2, or another number?
  • Write down the numbers you see. This helps you figure out what comes next.
  • Don’t rush! Take your time to look carefully.

Questions to Practice

Easy Level Questions

  1. 1, 2, 3, __, __
  2. 5, 6, __, __, 9
  3. 10, 11, __, __, 14
  4. 20, 21, __, __, 24
  5. 3, 4, 5, __, __
  6. 7, 8, __, __, 12
  7. 15, 16, __, __, 19
  8. 30, 31, __, __, 34
  9. 0, 1, __, __, 4
  10. 12, 13, __, 15, __

Medium Level Questions

  1. 2, 4, 6, __, __
  2. 5, 10, 15, __, __
  3. 3, 6, 9, __, __
  4. 10, 20, __, __, 50
  5. 1, 3, 5, __, __
  6. 25, 20, __, __, 10
  7. 18, 16, __, __, 12
  8. 33, 36, __, __, 42
  9. 52, 57, __, __, 67
  10. 60, 50, __, __, 30

Hard Level Questions

  1. 1, 3, 5, 7, __, __
  2. 10, 15, 20, 25, __, __
  3. 2, 5, 8, 11, __, __
  4. 100, 90, 80, __, __
  5. 25, 30, 35, 40, __, __
  6. 6, 12, 18, __, __
  7. 70, 65, 60, __, __
  8. 40, 30, 20, __, __
  9. 37, 34, 31, __, __
  10. 48, 56, 64, __, __

Answers and Explanations

Easy Level Answers

  1. 4, 5: You count up from 3, adding 1 each time.
  2. 7, 8: You continue the counting sequence from 6.
  3. 12, 13: You are counting up from 11 by adding 1.
  4. 22, 23: You are counting up from 21 by adding 1.
  5. 6, 7: You are counting up from 5 by adding 1.
  6. 9, 10: You are counting up from 8 by adding 1.
  7. 17, 18: You are counting up from 16 by adding 1.
  8. 32, 33: You are counting up from 31 by adding 1.
  9. 2, 3: You are counting up from 1 by adding 1.
  10. 14, 16: You are counting from 13, adding 1 to get 14, and then 1 more.

Medium Level Answers

  1. 8, 10: The pattern is counting by 2s.
  2. 20, 25: You are adding 5 to each number.
  3. 12, 15: You are adding 3 each time.
  4. 30, 40: You are counting by 10s.
  5. 7, 9: You are counting by 2s, adding 2 each time.
  6. 15, 10: You are counting down by 5.
  7. 14, 10: You are counting down by 2.
  8. 39, 42: You are adding 3 each time.
  9. 62, 67: You are adding 5 each time.
  10. 40, 30: You are counting down by 10.

Hard Level Answers

  1. 9, 11: You are counting up by 2s.
  2. 30, 35: You are adding 5 each time.
  3. 14, 17: You are adding 3 each time.
  4. 70, 60: You are counting down by 10.
  5. 45, 50: You are adding 5 each time.
  6. 24, 30: You are adding 6 each time.
  7. 55, 50: You are counting down by 5.
  8. 10, 0: You are counting down by 10.
  9. 28, 25: You are counting down by 3.
  10. 72, 80: You are adding 8 each time.

Now you are ready to complete sequences! Keep practicing and you will get better at it!