你的题目应该有误吧,个人觉得应该是18.8×5.8+7.2×4.2+11.6×4.2,如此解答
18.8×5.8+7.2×4.2+11.6×4.2
=18.8×5.8+(7.2+11.6)×4.2
=18.8×5.8+18.8×4.2
=18.8×(5.8+4.2)
=18.8×10
=188
不然(18.8 × 5.8) + (7.2 × 42) + (11.6 × 4.2) = 18.8×5.8+(72+11.6)×4.2
=18.8×5.8+83.6×4.2
=109.04+351.12
=460.16
18.8乘以5.8加7.2乘以4.2加11.6乘以4.2
=18.8*5.8+(7.2+11.6)*4.2
=18.8*5.8+18.8*4.2
=18.8*(5.8+4.2)
=18.8*10
=188
188