3×5=15, 9+36=45, 29+11=40, 92-12=80,
4×2=8, 21-12=9, 1×2=2, 11+88=99,
5×4=20, 1×1=1, 27厘米+30厘米=57厘米, 62+9=71,
58-19=39, 25+30+5=60, 84-8-60=16, 48+20-9=59.
3×5=15, 9+36=45, 29+11=40, 92-12=80,
4×2=8, 21-12=9, 1×2=2, 11+88=99,
5×4=20, 1×1=1, 27厘米+30厘米=57厘米, 62+9=71,
58-19=39, 25+30+5=60, 84-8-60=16, 48+20-9=59.