两个因数的积是12.48,其中一个因数是1.3,另一个因数是9.6
一个数的7倍是45.5,这个数的3倍是19.5
(1)7.92÷(1.7+1.6)
=7.92 ÷ 3.3
=2.4
(2)(25.8-17.14)×1.05
=8.66 ×1.05
=9.093
(3)4.3×9.9
=4.3×(10-0.1)
=4.3×10 -4.3×0.1
=43 - 0.43
=42.57
(4)1.25×6.4×2.5
= 1.25×(8×2×0.4)×2.5
=1.25×8 ×2×0.4×2.5
=10 ×2 ×1
=20
(5)0.18÷0.45×(1-0.9)
=0.4×0.1
=0.04
(6)17.2×0.54-0.54×7.2
=0.54×(17.2-7.2)
=0.54×10
=5.4