Explanation for Question 7 From the Math (Calc) Section on the 2019 May Sat
So question seven states in the table above the ratio of why 2 to X, for each ordered pair is constant. 3 What is the value of K? So, 4 because the ratio is constant, 5 that means that you can always multiply X by the same thing to get 6 Y so let's start by finding the ratio of Y to X. 7 So when X is equal to one, 8 Y is equal to four. So the ratio of Y to X is four 9 over one. Why is four X as one? 10 Now we can set that ratio equal to K over 40 11 in order to solve for K. 12 And we can do that because the ratio of Y to X is constant. 13 Now to solve this, we can cross multiply. 14 So 40 times four is equal to K and 15 we get K is equal to one 60. 16 And so the answer here is D.