Chloe and Daniel made six
cupcakes. After their dog ate some, there
were two left. They want to know how many cupcakes
their dog ate. Who is correct? Chloe says: We can solve two plus
what equals six. Daniel says: We can solve six take
away two equals what.
We know that Chloe and Daniel had
six cupcakes to begin with. We can model this using six
counters in a 10 frame. We also know that after their dog
ate some, there were two cupcakes left, so we know that one of the parts in our
part–whole model is the number two. They had six cupcakes. Their dog ate some. And they have two left. Chloe says we can solve two plus
what equals six. If we know that two plus four makes
six, Chloe must be correct. And if we look at our 10 frame, we
can see that there are two counters and four counters have been crossed out, but
there are six counters altogether. Two and four are a pair of numbers
which go together to make six. So Chloe is correct.
Daniel said we could solve six take
away two. He’s also correct. If two plus four equals six and six
take away two equals four, addition and subtraction are related. So if Chloe and Daniel made six
cupcakes, their dog ate some, and they had two left, they can work out how many
cupcakes their dog ate by either solving two plus four equals six or six take away
two equals four. They’re both correct.