PARCC 2016 Released Math Items: "Which Equation Shows the Relationship..."

What in the world is a relationship when you talk about math?

I know what a relationship is between friends, boyfriends, and parents... but what do they mean when they ask me about relationships in math ?

Since I know that the orca whale is 30 feet long, I can use that fact to help me know how long is the blue whale's length.

That's the relationship between the two lengths.

I think drawing a comparison model helps student see the relationship too.

Does anyone think about it differently than that? Especially when you are explaining a math relationship 

to a 10 year old child in 4th Grade. 

Smile,

Deborah