Subtract a multiple of 10

key notes :

Understand Multiples of 10

• A multiple of 10 ends in zero (e.g., 10, 20, 30, 40).

Recognize the Pattern

• When subtracting multiples of 10, only the tens place changes. The ones place remains the same.
  Example: 50 − 20 = 30.

Use Visual Aids

• Use number lines or base-10 blocks to help students see the subtraction process.

Simplify with Mental Math

• Teach students to focus on subtracting the tens digits.
  Example: In 70−30, subtract 7−3, then add a zero to get 40.

Real-Life Examples

• Frame word problems that involve subtracting multiples of 10, such as money or objects in groups of 10.

Practice with Counting Backward

• Encourage students to count backward in tens from the starting number.
  Example: 80 − 10 = 70 , 70 − 10 = 60 , and so on.

Relate to Addition

• Reinforce that subtraction is the inverse of addition.
  Example: 40 + 30 = 70, so 70 − 30 = 40.

Introduce Zero Concept

• Highlight that subtracting the same number results in zero.
  Example: 30 − 30 = 0.

Learn with an example

Let’s practice!