（3/4）/12+56x3/14=1/16+12=12又1/16
3/4 x 3/4-1/(8/3)=9/16+3/8=15/16
5/7x=35,x=49,10％x=4.9
3/2吨小麦可以磨面粉9/8吨,求磨一吨面粉需要小麦的吨数,列式为9/8 /(3/2)=4/3