Video Transcript
Complete the following: Two divided
by what equals one.
In this question, we’re given a
division with a missing number. What do we divide two by to give us
the answer one? Well, we know that division and
multiplication are inverse operations; they’re opposites. So to help find a missing number in
a division like this, we can think about the multiplication fact that goes with it,
the opposite of it. So instead of asking ourselves,
“What do we divide two by to give us the answer one?”, we can work backward and ask
ourselves, “What do we multiply one by to give us the answer two?” Well, this is quite a simple
multiplication fact, isn’t it? One times two equals two. And if we know there’s one lot of
two in two, if we divide to by itself, we’re going to get the answer one.
Another way we know this is true is
because we know a rule that applies every time a number is divided by itself. Any number divided by itself equals
one. And so, because our division showed
the answer one, we knew that the first number must be divided by itself. Two divided by two equals one. Our missing number is two.