120 , I think ......................
The last one isn’t
there can’t be more than 1 of the same x value
6a+12=2(3a-8)
6a+12=6a-16
-12. -12
6a=6a-4
-6a -6a
0=-4
no solution because the equation is false.
A rate often involves time: e. g., 33 feet per second; also, we are finding the ratio of one type of measurement with respect to another: distance and time.
A proportion is often the ratio of different measures of the same thing:
e. g. 5 apples
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7 apples