Mary has x dollars more than Kathy has, and together they have a total of y dollars. Which of the following represents the number of dollars that Kathy has? Choose the correct answer
A) (y – x)/6 B) (y – x)/5 C) 5(y – x)/2 D) 3(y – x)/2 E) (y – x)/2
To solve, we will set up two equations. Let's start by defining two variables.   A = number of dollars Kathy has   B= number of dollars Mary has   We are given that Mary has x dollars more than Kathy. We set up an equation:   B= x + A   We are next given that together they have a total of y dollars. We can set up our second equation:   A + B = y   Since we know that B = x + A, we can substitute x + A for B into the second equation A+ B = y.   Notice that, after the substitution, we will only have variables of A, x, and y. Thus, we have:   A + x + A = y   2A + x = y   2A = y – x   A = (y – x)/2   Answer : (y – x)/2
<result>E</result>
Mary has x dollars more than Kathy has, and together they have a total of y dollars. Which of the following represents the number of dollars that Kathy has?