1.  If x + y = 13 and 5 x  y = 5, then x  y is equal to 

Hint
Halfnhalf Clue
 

2.  A university has 2000 graduate students. The number of undergraduate students is 4 / 3 times the number of graduate students. What fraction of the students in the university are undergraduates? 
 Halfnhalf Clue
 

3.  Consider a square with side of length a, and an an isosceles right triangle with one side of length a and hypotenuse of length b. What is the sum of the areas of the square and the triangle? 
 Halfnhalf Clue
 

4.  There are 520 animals on a farm. Threefourths of them are cows. Of the cows, about 60% are white. How many cows on the farm are not white? 
 Halfnhalf Clue
 
