(1)十÷十又十一分之十+二十四又十二分之一÷12
=10÷[10x(1+1/11)]+(24+1/12)×1/12
=1÷12/11+2+1/144
=11/12+1/144+2
=133/144+2
=2又144分之133
(2)五分之四×三分之一+5.2×三分之一+1÷四分之三
=(0.8+5.2)x1/3+1x4/3
=2+4/3
=3又3分之1
(3)0.25×12.5÷三十二分之一
=0.25x12.5x32
=0.25x4x(12.5x8)
=1x100
=100
(4)(1986分之1985)×999
=(1-1/1986)x999
=999-999/1986
=999-333/662
=998又662分之329
同学,否则我都不敢继续给你作答了,因为不采纳我得不到分数的