二又八分之一除以中括号五分之三乘小括号十六分之十一减零点5
=17/8÷[3/5×(11/16-0.5)]
=17/8÷[3/5×(11/16-1/2)]
=17/8÷[3/5×(11/16-8/16)]
=17/8÷(3/5×3/16)
=17/8÷9/80
=17/8×80/9
=170/9
=18又9分之8