Explanation for Question 33 From the Math (Calc) Section on the 2018 May Sat
Question 33 says the profit P in dollars from producing 2 and selling end units of a certain product is given by the equation above 3 where K is a constant, if 200 units are produced and sold 4 for a profit of $1,275, 5 what is the value of K? So this is giving us everything that we 6 can plug into the equation so that Katie is the only variable left. 7 So we know that P is equal to 1,275 and 8 is equal to 200 and we can use that to 9 solve for Kevin. So as you can see here, 10 I've just filled in the numbers and for those variables, 11 because we were given those values and now I'm going to solve. 12 So this can be rewritten. As 1,275 is equal to 1,800 13 minus 400 plus K. 14 And then I can rewrite this as 1,275 is equal to 15 1,400 minus K. 16 And finally, I'm going to add K to both sides and subtract 1,275 17 from both sides. And that gives me K is 18 equal to 125, 19 which is our final answer.