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numbers:
+
+
×
×
÷
÷
allow self-correction (print results, if possible)

Settings

Calculate
crossing the tens barrier
draw elements
round up: 
comma: 
negative numbers
 
a + ? = c
a + b + c = ?
(a + b) • c = ?
multiplication & division:
×
1234567891011+
Unused / Future extension
Geometry, units, precision & options
geometry: 
lengths
perimeters
areas
volumes
weights
liquids
also triangles
also circles
angles: 
clock: 
money: