数学听课 mind

10.5 数学， 进位

What am I gonna do first?

Everybody in this room what am I going to do first?

I’m going to add one side.

What’s in the oneside ,Alayna? 3and 7 chrissee ,what is 3 plus 7?

Now ,think about number 10.What do I do next?

I need to figure out.what digit am I going to put there?

The zero .Why am I going to put the zero?

The zero is in the ones place

• • • •

Even though it’s a zero , I still need to put it in.

So zero goes here.

What am I gonna do next?

Cade , remember we have the number ten, 3 plus seven makes ten. I put my zero here, where does that digit go ? Where ? Right here ? Right here ?no , not quite.

Cade , we will put 1 right up here. Because 3 plus 7 equals ten.thinking about my ten. I can’t just leave the number 1 . We couln’t put two digit in one column.so I need to take the 1 because the tens place in the number 10 and keep it in the ten place. Now what am I gonna do , D? And what’s the answer ?

All right , I ‘m going to start calling people and come up and write for me .

Everyone need to start to put on their thinking cap and sit on their bottom.

I want you to tell us what are you doing while you are doing that.

You can do that.

Who can tell me why he put the 4 over there?

Because in the number 14, 4 is in the ones place.