432.1×123.4-432.2×123.3
=432.1×123.4-(432.1+0.1)×123.3
=432.1×123.4-432.1×123.3-0.1×123.3
=432.1×(123.4-123.3)-12.33
=432.1×0.1-12.33
=43.21-12.33
=30.88
432.1×123.4-432.2×123.3
=432.1×123.4-(432.1+0.1)×123.3
=432.1×123.4-432.1×123.3-0.1×123.3
=432.1×(123.4-123.3)-12.33
=432.1×0.1-12.33
=43.21-12.33
=30.88