Answer:
x=3
Step-by-step explanation:
(scroll)
a:b = xb:b
a+40:b+40 = 7:3
a+40/b+40=7/3
3(a+40)=7(b+40)
3a+120=7b+280
3a=7b+160
160=3a-7b
a-40:b-40 = 5:1
a-40/b-40=5/1
a-40=5(b-40)
a-40=5b-200
a=5b-160
3a=15b-480
-480=3a-15b
160=3a-7b - (-480=3a-15b)
640=8b
b=80
160=3a-7(b)
160=3a-7(80)
160=3a-560
720=3a
a=240
x*80=240
x=3
(The numbers seem to work so I think this is right!)