Sequences – count up and down by 100

Key notes:

🔢 What is a Sequence?

  • A sequence is a set of numbers in a special order.
  • Example: 100, 200, 300, 400… ⬆️ (Counting up)

⬆️ Counting Up by 100:

  • Start from any number.
  • Add 100 each time.
  • Example: 100, 200, 300, 400, 500…
  • 🎉 Tip: Look at the hundreds place – it goes 1, 2, 3, 4…

⬇️ Counting Down by 100:

  • Start from a bigger number.
  • Subtract 100 each time.
  • Example: 500, 400, 300, 200, 100…
  • 🎈 Tip: The hundreds place goes backward 5, 4, 3, 2…

✨ Fun Practice:

Fill the missing numbers:

  • 100, __, 300, __, 500 ⬆️
  • 900, __, 700, __, 500 ⬇️

🎨 Remember with Colors:

  • Use red 🔴 for hundreds that are counting up.
  • Use blue 🔵 for hundreds that are counting down.

💡 Quick Trick:

  • Counting up by 100 → add 1 to the hundreds place.
  • Counting down by 100 → subtract 1 from the hundreds place.

Learn with an example

🚀Type the missing number in this sequence:

300, 400, 500, 600,_______

  • First, look for a pattern. Notice how each number is 100 more than the previous number:
  • 300, 400, 500, 600, __
  • To make the pattern complete, the number 700 must go in the blank space.

🚀 Type the missing number in this sequence:

200, 300, 400, 500,_____, 700, 800

  • First, look for a pattern. Notice how each number is 100 more than the previous number:
  • 200, 300, 400, 500, __, 700, 800
  • To make the pattern complete, the number 600 must go in the blank space.

🚀Type the missing number in this sequence:

200, 300,____, 500, 600, 700, 800

  • First, look for a pattern. Notice how each number is 100 more than the previous number:
  • 200, 300, __, 500, 600, 700, 800
  • To make the pattern complete, the number 400 must go in the blank space.

Let’s practice!