X-X/4+1/5X=95
X-1/4X+1/5X=95
X-5/20X+4/20X=95
19/20X=95
X=95÷19/20
X=95×20/19
X=100
1.25：0.25=X：3.2
X=1.25÷0.25×3.2
X=16
4/9X+0.5=13/9X-1.3
13/9X-4/9X=1.3+0.5
X=1.8
4/7X÷2/3=4/7
4/7X=4/7 ×2/3
X= 2/3
(7又5/7-0.8+2又2/7)×12.5
=(54/7+16/7-4/5)×25/2
=38/7×25/2-4/5×25/2
=950/14-10
=810/14
=57又6/7