Add using doubles plus one

Key notes:-

🔢 What are Doubles?

  • Doubles are when we add the same number to itself.
    👉 Example: 4 + 4 = 8, 5 + 5 = 10

➕ What is Doubles Plus One?

When the second number is one more than the first number.

Instead of adding normally, we can use the double and then add 1 more.
👉 Example: 4 + 5

  • Double of 4 is 8
  • Then add 1 more → 9

🌈 Why Use Doubles Plus One?

  • It makes adding faster and easier!
  • Helps students solve addition facts mentally.
  • Builds confidence in basic math skills.

🧠 How to Spot a Doubles Plus One Fact

Look for numbers like:

  • 3 + 4
  • 6 + 7
  • 8 + 9
    The numbers are side-by-side (one bigger by 1).

✨ Steps to Solve (Super Easy!)

1️⃣ Find the smaller number.
2️⃣ Double it.
3️⃣ Add 1 more!

👉 Example: 7 + 8

  • Double 7 = 14
  • Add 1 = 15

🍎 Common Doubles Plus One Facts

ProblemThink DoubleAnswer
2 + 32 + 2 + 15
3 + 43 + 3 + 17
5 + 65 + 5 + 111
8 + 98 + 8 + 117

🎨 Visual Reminder

Doubles → twins 👯
Doubles + 1 → twins with one extra friend 😊

🎉 Practice Examples

Try these using the doubles plus one trick:

  • 6 + 7
  • 4 + 5
  • 9 + 8
  • 1 + 2

Learn with an example

🖊️Add the near doubles.
Hint: use the doubles fact 2 + 2 = 4.
2 + 3 =

  • To add 2 + 3, you can use the strategy of doubles plus one. This is because 2 and 3 are near doubles.
  • Break 3 into 2 + 1 to make double 2s.
  • 2 + 3 = 2 + 2 + 1
  • Add the double 2s. Use the doubles fact 2 + 2 = 4.
  • 2 + 2 + 1 = 4 +1
  • Add 1.
  • 4 + 1 = 5
  • So, 2 + 3 = 5.

🖊️Add the near doubles.
Hint: use the doubles fact 3 + 3 = 6.
3 + 4 =

  • To add 3 + 4, you can use the strategy of doubles plus one. This is because 3 and 4 are near doubles.
  • Break 4 into 3 + 1 to make double 3s.
  • 3 + 4 = 3 + 3 + 1
  • Add the double 3s. Use the doubles fact 3 + 3 = 6.
  • 3 + 3 + 1 = 6 + 1
  • Add 1.
  • 6 + 1 = 7
  • So, 3 + 4 = 7.
  • So, 2 + 3 = 5.

🖊️Add the near doubles.
Hint: use the doubles fact 5 + 5 = 10.
5 + 6 =

  • To add 5 + 6, you can use the strategy of doubles plus one. This is because 5 and 6 are near doubles.
  • Break 6 into 5 + 1 to make double 5s.
  • 5 + 6 = 5 + 5 +1
  • Add the double 5s. Use the doubles fact 5 + 5 = 10.
  • 5 + 5 + 1 = 10 + 1
  • Add 1.
  • 10 + 1 = 11
  • So, 5 + 6 = 11.

let’s practice!