Mathematics workshop
Subtraction
Take a part away from a whole. See what remains and check by adding.
It helps to understand parts, whole and addition.
Theory
Take away a part
Remove two counters from five, then restore them. After removal, three remain: 5 − 2 = 3. Restoring checks the answer: 3 + 2 = 5.
5 − 0 = 5
Before: 5
Removed: 0
Remaining: 5
Subtract: move left
Start at 7. To subtract 4, take four steps to the left, one at a time: 6, 5, 4, 3. The numbers get smaller. Each arc is one step. The right button undoes a step; Reset takes you back to 7.
7 − 0 = 7
Start: 7Steps: 0 / 4Now: 7
Take away the whole
Remove all four counters: zero remain, 4 − 4 = 0. Then restore the whole. There will be four again.
4 − 0 = 4
Before: 4
Removed: 0
Remaining: 4
An empty whole
An empty collection has zero counters. Take away none and zero remain: 0 − 0 = 0. For now, take away only what is there.
0 − 0 = 0
Before: 0
Removed: 0
Remaining: 0
Practice
Change the whole and the part taken away. Compare the remaining objects with the equation.
2 − 1 = 1
Before: 2
Removed: 1
Remaining: 1
Click a number to choose a new start. Change the step count below.
Games
Find what remains or a missing number. Answers in these tasks are never negative.
?
Click a number to check your answer straight away.