Ethan is subtracting from six. Write the missing sentence. Six take away one is five. Six take away two is four. What? Six take away four is two. And six take away five is one.
In this question, we’re told that
Ethan is subtracting from six. And if we look carefully, we can
see he’s trying to find all the possible ways to take away from six. He starts with a very small number,
so he takes away one. Then he takes away one more, so he
takes away two. In our third example, we can see
that Ethan takes away one, two, three counters. Of course he does. This is one more than two. So he starts off with six and he
takes away three. And he continues going through all
the different subtractions, taking away four and finally five.
But we want to think particularly
about this middle subtraction. Six take away three is what? You know, we could use a part
whole–model to help us here. In each of these pictures and each
of these number sentences, the whole amount is six. This is the amount that Ethan
starts with. Now, when Ethan takes away one
counter to begin with, he’s left with five. And we know this because one and
five are two parts that go together to make six. He takes away two then. He’s left with four because two and
four go together to make six.
So now he wants to take away
three. All we have to do is think about
what part goes with three to make six. And we know that three and another
three make six. And so we can complete our number
sentence. Six take away three is three. We’ve followed Ethan’s pattern to
find the missing number sentence. And that was six take away three is