Skip to content

Learn

Subtraction

Level 23 / realistic untimed

4d - 3d (cascade borrow)

5 visual steps / borrow-window subtraction

1. Release thousands

1. Release thousandsRelease one digit; only borrow stays active.
answer strip
6 - 0 = 6; drop 6.

6 - 0 = 6; drop 6.

2. Release hundreds

2. Release hundredsRelease one digit; only borrow stays active.
answer strip
Pay right borrow; release 4: 8 - 3 - 1 = 4.

Pay right borrow; release 4: 8 - 3 - 1 = 4.

3. Release tens

3. Release tensRelease one digit; only borrow stays active.
answer strip
Borrow 10; pay right borrow: 11 - 5 - 1 = 5.

Borrow 10; pay right borrow: 11 - 5 - 1 = 5.

4. Release ones

4. Release onesRelease one digit; only borrow stays active.
answer strip
Borrow 10; release 5: 12 - 7 = 5.

Borrow 10; release 5: 12 - 7 = 5.

5. Read answer

5. Read answerRelease one digit; only borrow stays active.Read answerDrop finished digits; borrow is gone.
Read 6 | 4 | 5 | 5 as 6455; borrow is gone.

Read 6 | 4 | 5 | 5 as 6455; borrow is gone.

Practice Level 23

A few quick rounds make each dropped digit feel light; borrow is the only thing to keep.

Start Level