Mason and his children went into a movie theater and he bought $36.50
worth of candies and pretzels. Each candy costs $4.25 and each pretzel costs
$3.50. He bought 6 more pretzels than candies. Write a system of equations
that could be used to determine the number of candies and the number of
pretzels that Mason bought. Define the variables that you use to write the
system.