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Soroban subtraction drills (2 digits)

Subtraction is where abacus learners lose the most marks — the complements run backwards and the borrow travels the other way.

  • 5 rows × 2 digits, subtraction
  • About 7 min
  • Free, no account

Sample problems

Real problems from this drill, with answers. Nothing to install, no account, no email — work them on paper, on a physical abacus, or in your head.

  1. 1
    181
    − 54
    − 53
    − 47
    − 22
    ?
  2. 2
    254
    − 94
    − 21
    − 13
    − 85
    ?
  3. 3
    318
    − 54
    − 64
    − 85
    − 47
    ?
  4. 4
    170
    − 14
    − 29
    − 98
    − 22
    ?
  5. 5
    305
    − 43
    − 98
    − 29
    − 61
    ?
  6. 6
    264
    − 15
    − 84
    − 33
    − 45
    ?
  7. 7
    286
    − 89
    − 36
    − 41
    − 28
    ?
  8. 8
    164
    − 50
    − 49
    − 14
    − 28
    ?
  9. 9
    225
    − 43
    − 66
    − 36
    − 61
    ?
  10. 10
    192
    − 62
    − 23
    − 89
    − 16
    ?
Full answer key
  1. 181 − 54 − 53 − 47 − 22 = 5
  2. 254 − 94 − 21 − 13 − 85 = 41
  3. 318 − 54 − 64 − 85 − 47 = 68
  4. 170 − 14 − 29 − 98 − 22 = 7
  5. 305 − 43 − 98 − 29 − 61 = 74
  6. 264 − 15 − 84 − 33 − 45 = 87
  7. 286 − 89 − 36 − 41 − 28 = 92
  8. 164 − 50 − 49 − 14 − 28 = 23
  9. 225 − 43 − 66 − 36 − 61 = 19
  10. 192 − 62 − 23 − 89 − 16 = 2

This page is one drill. The app is the whole programme.

Kani Math is a full mental-arithmetic course, not a single exercise. Free to start, no signup, and it runs on the web, Android and iPhone.

  • ✓Nine levels, from the first bead to division
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  • ✓Versus matches against friends or the computer
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  • ✓Streaks, coins and badges, with parent and teacher views

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Practise it now

The same drill, live in your browser, with a virtual soroban and instant marking.

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Explore the free virtual abacus →How to use an abacus →Mental Math Drill →

About this drill

Every complement rule has a subtraction twin, and the twins are where errors concentrate. To subtract 8 from a rod showing 3, you remove ten from the rod on the left and give back two — the mirror of the addition rule, using the same pair. Learners who memorised the addition rules as procedures rather than as pairs have to relearn everything here; learners who memorised the pairs get subtraction almost free.

Each problem below starts from a number large enough that four subtractions never take the total below zero, because a soroban cannot show a negative. That constraint is not a simplification — it is how the instrument works, and it shapes how subtraction is taught.

How to practise it

  1. 1Set the starting number, then work down the column.
  2. 2For each row ask "is the bead free?" before reaching for a complement.
  3. 3Borrow ten from the left rod, then give back the complement.
  4. 4The total never goes below zero — if it does, you made an error.

Questions

Why can the answer never be negative?
A soroban has no sign — a bead is either counted or not. Working below zero requires a separate complement-of-the-whole-number technique taught much later.
Is subtraction harder than addition?
It is the same rules run backwards, but most curricula spend far less time on it, so it feels harder. Equal practice time closes the gap quickly.
What is the most common mistake here?
Giving back the wrong complement — subtracting ten and then subtracting the remainder instead of adding it. Slow, deliberate reps fix it.
Can I mix addition and subtraction?
Yes, and you should once each is solid on its own. The mixed drill page covers exactly that.
Learn the techniqueBig friends (10-complements)Walk through it on the beads →