The competition discipline: numbers flashed faster than you can name them, added on an abacus that exists only as an image.
5 rows × 2 digits, addition
About 8 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
22
+ 66
+ 26
+ 93
+ 75
?
2
29
+ 96
+ 63
+ 36
+ 12
?
3
52
+ 95
+ 30
+ 97
+ 17
?
4
76
+ 60
+ 28
+ 70
+ 43
?
5
81
+ 16
+ 46
+ 90
+ 22
?
6
44
+ 38
+ 27
+ 67
+ 85
?
7
28
+ 93
+ 89
+ 77
+ 82
?
8
12
+ 88
+ 53
+ 94
+ 90
?
9
26
+ 27
+ 76
+ 38
+ 72
?
10
62
+ 92
+ 21
+ 23
+ 18
?
Full answer key
22 + 66 + 26 + 93 + 75 = 282
29 + 96 + 63 + 36 + 12 = 236
52 + 95 + 30 + 97 + 17 = 291
76 + 60 + 28 + 70 + 43 = 277
81 + 16 + 46 + 90 + 22 = 255
44 + 38 + 27 + 67 + 85 = 261
28 + 93 + 89 + 77 + 82 = 369
12 + 88 + 53 + 94 + 90 = 337
26 + 27 + 76 + 38 + 72 = 239
62 + 92 + 21 + 23 + 18 = 216
Practise it now
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About this drill
Flash anzan is what mental abacus training builds towards. Numbers appear for a fraction of a second each, far too fast to verbalise, and the learner adds them on a soroban held entirely in visual working memory. Because the image is spatial rather than verbal, the numbers can arrive faster than inner speech — which is precisely why trained learners outrun anyone using a language-based method.
It only works if the mental image is already stable. Attempting flash anzan before three-digit mental addition is reliable produces guessing dressed up as speed, and the habit is hard to unlearn. If accuracy here is below about 80%, slow the interval rather than pushing through.
How to practise it
1Confirm three-digit mental addition is reliable before starting.
2Fix your gaze; do not track the numbers with your eyes.
3Build the bead image once and move it — do not rebuild it each flash.
4Raise speed only when a full set comes back clean.
Questions
What speeds are realistic?
A learner two or three years in typically handles 5 two-digit numbers at around 0.4 seconds each. Competitive flash anzan goes well below 0.2, but that is a specialist pursuit.
Do I need to have used a physical abacus?
In practice, yes. The mental image is a memory of a real instrument; learners who start from a picture rather than from bead handling rarely build a stable one.
Why does saying the numbers slow me down?
Because inner speech is serial and roughly caps at three or four items a second. The bead image is not verbal, so it is not bound by that limit.
Is this useful, or just impressive?
Both, honestly. The transferable part is the working-memory training; the speed itself is mostly a by-product that happens to be very motivating for children.