Answer:
Proportions:
18/8 and 9/4
4/7 and 10/17.5
<em>Everything else is not a proportion</em>
Step-by-step explanation:
To find if two fractions are a proportion, we need to set each up as a fraction. Then, we multiply both diagonal values. If we get the same value, they are proportionate.
and
:
![12\cdot 2= 24\\\\9 \cdot 3 = 27\\\\24 \neq 27](https://tex.z-dn.net/?f=12%5Ccdot%202%3D%2024%5C%5C%5C%5C9%20%5Ccdot%203%20%3D%2027%5C%5C%5C%5C24%20%5Cneq%2027)
So these aren't proportionate.
and
:
![141\cdot 3 = 423\\\\8 \cdot 6 = 48\\\\48 \neq 423](https://tex.z-dn.net/?f=141%5Ccdot%203%20%3D%20423%5C%5C%5C%5C8%20%5Ccdot%206%20%3D%2048%5C%5C%5C%5C48%20%5Cneq%20423)
So these aren't proportionate either.
and
:
![18 \cdot 4 = 72\\\\9 \cdot 8 = 72\\\\72 = 72](https://tex.z-dn.net/?f=18%20%5Ccdot%204%20%3D%2072%5C%5C%5C%5C9%20%5Ccdot%208%20%3D%2072%5C%5C%5C%5C72%20%3D%2072)
So this is proportionate.
(since 775 is just that over 1) and
:
![775 \cdot 20 = 15500\\\\1 \cdot 27 = 27\\\\27 \neq 15500](https://tex.z-dn.net/?f=775%20%5Ccdot%2020%20%3D%2015500%5C%5C%5C%5C1%20%5Ccdot%2027%20%3D%2027%5C%5C%5C%5C27%20%5Cneq%2015500)
So this isn't proportionate.
and ![\frac{10}{17.5}](https://tex.z-dn.net/?f=%5Cfrac%7B10%7D%7B17.5%7D)
![4\cdot 17.5 = 70\\\\7 \cdot 10 = 70\\\\70 = 70](https://tex.z-dn.net/?f=4%5Ccdot%2017.5%20%3D%2070%5C%5C%5C%5C7%20%5Ccdot%2010%20%3D%2070%5C%5C%5C%5C70%20%3D%2070)
So this is proportionate.
Hope this helped!