x/880+x/760=9 41x/16720=9x=150480/41（3/8+2/5）*8+9/27=3/8*8+2/5*8+1/3=3+3又1/5+1/3=6又1/5+1/3=6又8/150.36+0.64÷1.6=0.36+0.64÷0.8÷2=0.36+0.8÷2=0.36+0.4=0.76还有一个，，（8.5-4）÷（0.32÷1.6）这个，如何简便？（8.5-4）÷（0.32÷1.6）=4.5×1.6÷0.32=4.5×（1.6÷0.32）=4.5×5=22.5