Multiplication strategies

- [Teacher] We're told here

is a partially completed
multiplication table

and we could see they go all the way up to

the four times tables, I
guess you could call it that.

And they want us to figure
out what eight times six is.

So pause this video, have a go at that

before we do this together.

Okay, so let's think about
where eight times six is

on this multiplication table.

So if we say six times
eight, it is over here,

because we know that eight times six

is the same thing as six times eight.

Or we could think about
eight times six exactly

as it's written here, which I would say

is this square right over here.

So what are ways that we could figure out

what goes in these?

And the same number should
go into both of these.

Well, one way is to look right over here

where they tell us what four times six is.

We see that four times six is equal to 24.

So based on that we
could say eight times six

is going to be twice as much as that.

So if we multiply this by two,

or another way to think about it,

if we added another 24 over here,

we're going to get to eight times six.

So 24 plus 24, you might recognize

as being equal to 48.

So that's one way you
could have done that.

You could have said that is 48.

Another way that you
could have approached this

is you could have tried
to fill this one in,

and you could have said, okay,

if we're going down this column,
every time we go down one,

we're increasing by eight

'cause we're going larger and
larger multiples of eight.

So eight times five we
would add eight again,

we would get to 40.

And then if we add eight another time,

we would get to 48.

So these are all ways to do it.

You could also go down
this column right over here

and add six every time.

And you could see that that would work.

If you add six to 24, you'd get 30,

add six to that, you get
36, add six to that 42,

add six to that, you get 248.