Question

15.5+24.5×8.6用简便计算？

Answer 1

15.5+24.5×8.6
=15.5+（40-15.5）*8.6
=15.5+40*8.6-15.5*8.6
=40*8.6-15.5*7.6
=320+24-31*3.8
=344-（30+1）*3.8
=344-30*3.8-3.8
=344-90-24-3.8
=230-3.8
=226.2

Answer 2

15.5+24.5*8.6=
15.5+24.5(10-1-0.4)=
15.5+245-24.5-98=
15.5+245-122.5=
260.5-122.5=138

Answer 3

15.5+24.5×8.6
=15.5+49×4.3
=11.2+4.3+49×4.3
=11.2+50×4.3
=11.2+215
=226.2

Answer 4

15.5+24.5x8.6
=5x3.1+5x4.9x8.6
=5[3.1+（5-0.1）x8.6]
=5（3.1+43-0.86）
=5x45.24
=226.2

Answer 5

15.5+24.5×8.6
=5×3.1+5×4.9×8.6
=15.5+24.5×8.6=226.2