Question

12.17×13.4-21.7×1.34的简便算法？

Answer 1

12.17×13.4-21.7×1.34
=12.17x13.4-21.7x1.34x10/10
=12.17x13.4-21.7/10x1.34x10
=12.17x13.4-2.17x13.4
=(12.17-2.17)x13.4
=10x13.4
=134

Answer 2

12.17×13.4-21.7×1.34
=121.7×1.34-21.7×1.34
=1.34×（121.7-21.7）
=1.34×100
=134