(3/8x-15)/(5/8x-15)=7:5
问题描述：
(3/8x-15)/(5/8x-15)=7:5
答
102*54-3780÷36
=5508-105
=5403
(39+39/61)÷39
=39÷39+39/61÷39
=1+1/61
=1又61分之1
(48-36*2/3)÷(1/4-1/5)
=(48-24)÷(1/20)
=24×20
=480
99*10.1
=99*101÷10
=(100-1)*(100+1)÷10
=(100²-1)÷10
=9999÷10
=999.9
答
内项积等于外项积
所以7(5/8x-15)=5(3/8x-15)
35/8x-105=15/8x-75
35/8x-15/8x=105-75
20/8x=30
x=30÷20/8
x=12