This is super easy!

Let's just do one:

1/3 x 9/10

We just multiply straight across...

Now, think about it...

1/3 x 9/10 is like 1/3 of 9/10 ...

Cut a pizza into 10 pieces

pizza cut into 10 equal pieces

and look at 9 of the pieces:

9 pieces of the pizza

We want 1/3 of these ( 1/3 of 9/10 )

That would be 3 pieces. Right?

That's 3/10!

Just what we got by doing the math! Cooooool.

Now that we get what's going on, we can just go for it.

Here's another one:

4/5 x 1/6