30×(五分之一+三分之一)
=30*(1/5+1/3)
=6+10
=16
四分之三×九分之一+四分之一÷9
=3/4*1/9+1/4*1/9
=1/9*(3/4+1/4)
=1/9
三分之二×七分之五+三分之二×七分之二
=2/3*5/7+2/3*2/7
=2/3*(5/7+2/7)
=2/3
5-(七分之六÷十四分之三+十六分之三)
=5-(6/7*14/3+3/16)
=5-(4+3/16)
=13/16
1、原式=30×(1/5)+30×(1/3)
=6+10
=16
2、原式=3/4×(1/9)+1/4×(1/9)
=(3/4+1/4)×(1/9)
=1×(1/9)
=1/9
3、原式=2/3×(5/7)+2/3×(2/7)
=2/3×(5/7+2/7)
=2/3×1
=2/3
4、原式=5-(6/7×14/3+3/16)
=5-(4+3/16)
=5-4-3/16
=1-3/16
=13/16