A yard is equal in length to three feet the function F (y) takes a measurement in yards (as input) and returns a measurement in feet (as output) if the output is 30 what was the input number

First let us answer it as if the input is 12. Then the output is 36. F (12) = 36 If the input is 13, then the output is 39. F (13) = 39 So we know the answer is between 36 and 39 The output of 12.5 is the same as the output of 12 plus the output of. 5 F (12.5) = F (12) + F (.5) = 36 + 1.5 = 37.5 So the question is really what is the output of. 2 F (12.2) = ... The same as Y=3X with X being the input.