standard_description: Use variables to represent numbers and write expressions when solving a real-world or mathematical problem; understand that a variable can represent an unknown number, or, depending on the purpose at hand, any number in a specified set.
problem_activity: A pitcher of water holds 48.2 ounces of water in it. The water is poured into two glasses, 12.08 ounces into one glass and 18.86 ounces into a second glass.
a.   How much water is poured out of the pitcher?
b.   How much water is left in the pitcher?


aligns: no