原式=(4.6+0.27+3.2-0.21)×(10-1/8)
=(4.6+3.2+0.27-0.21)×(10-0.125)
=(7.8+0.06)×(10-0.125)
=78.6+7.86×0.125
=78.6+0.9825
=79.5825.
简便算法：括号四点六加零点二七加三又五分之一减零点二一反括号乘括号十减八分之一
原式=(4.6+0.27+3.2-0.21)×(10-1/8)
=(4.6+3.2+0.27-0.21)×(10-0.125)
=(7.8+0.06)×(10-0.125)
=78.6+7.86×0.125
=78.6+0.9825
=79.5825.