"Porportional Relationships" means that the rate in which it increases is the same.
For example: 1, 3, 5, 7, 9 is a porportional relationship, because it increases each time by (+2).
Now, look at the first one.
From y to x, y being 2, x being 10, you divided 5 from x to get 2. Next, you divided 6 from 30 to get 5. Because the number dividing is different, it is not proportional
NOT PROPORTIONAL
Look at the second one.
From y to x, y being 12, x being 10, you divided 1.2
Now, look at the next one. 30/25 = 1.2
Finally, the last one. 48/40 = 1.2
Because all of them are 1.2, the answer is proportional
PROPORTIONAL
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