Operation
Practice type
Practice numbers in this range (remembered for next time)
to
Timing
0
correct
0
streak
∞
time left
7 × 6
Session complete
0
correct
0
wrong
0%
accuracy
0s
avg time
Overview
0
problems done
0%
accuracy
0
day streak
By operation
Times table heatmap
Greener = stronger. Tap a row/column number to drill it.
Achievements
Recent sessions
Addition & subtraction
- Make ten: break one number apart to round the other to a friendly ten. 8+5 → 8+2+3 = 10+3 = 13.
- ±9 (or ±11): add/subtract 10, then nudge back by 1. 47+9 = 57−1 = 56. 47−9 = 37+1 = 38.
- Left-to-right: for multi-digit sums, add the biggest place value first instead of starting from the ones column.
- Compensate: round one number to something easy, solve, then undo the adjustment at the end.
Multiplication
- ×5: multiply by 10, then halve. 14×5 = 140÷2 = 70.
- ×9: multiply by 10, then subtract the original number. 14×9 = 140−14 = 126.
- ×11 (two digits): add the two digits, drop the sum in the middle. 23×11 → 2+3=5 → 253.
- Double/halve: if one factor is even, halve it and double the other. 16×15 = 8×30 = 240.
- Squares ending in 5: n5² = n×(n+1) followed by 25. 35² → 3×4=12 → 1225.
Division
- Divisibility rules: by 2 (even), 3 (digit sum ÷3), 5 (ends 0/5), 9 (digit sum ÷9), 10 (ends 0).
- Simplify first: cancel common factors before dividing big numbers.
- Estimate, then refine: round to a nearby friendly number to gauge the size of the answer first.
Getting faster
- Trust your first instinct on facts you've overlearned — don't re-check what you already know cold.
- Drill one fact family at a time with By number so the pattern sticks before moving on.
- Little and often beats long cram sessions — that's what Weak facts and the Test Arena are built for.