Writing and evaluating expressions

5a. in may, zookeepers added grain to fiona's diet. she was eating c cups of grain per day. write an expression for how many days a supply of 120 cups of grain would last.

b. evaluate the expression she ate 1.5 cups of grain per day in may

An expression is basically an equation without the equal sign. An expression for your problem (part A) would be 120/c. For example, with the expression, we can see that if Fiona ate 40 cups of grain per day (120/3), then her grain would last her 3 days.

The way B is worded is a bit weird to me, but if I understand it correctly, Part B is simple now that we have the expression because we can plug in the value for the variable c. 120/1.5 is 80. If Fiona eats 1.5 cups of grain per day (much more reasonable than my exanple of 40 above, lol), then she would have grain for 80 days.