Project Math Access DVD 02 - Abacus- Part 05
Transcript Start
Audio Description: Part five; basic computation: braillewriter, abacus and calculator; example one.
TEACHER: Alright, now what we're going to do. So we've managed to do this problem with Unifix cubes and count up in our head. But we want to double check. We're going to talk about how we'll write in on the braillewriter, how we're going to check it on the Abacus and check in on the calculator. Okay. So we're going to step 2 of the problem. Okay. I need you to go down about two lines on your braillewriter.
[sound of braillewriter]
What were the two numbers that we were working with?
ALI: 161 and 160
TEACHER: Well, 161 was the original number. How much money did you give the cashier?
ALI: 2 dollars
TEACHER: Okay, what is our subtraction problem going to be?
ALI: 161, no, 2 dollars minus 161
TEACHER: I think we should write this down so we don't forget it.
Audio Description: Ali turns to the braillewriter.
What do you think? Yeah, probably a good idea.
ALI: So, dollar sign, number sign, 2.
TEACHER: Drop your 2.
ALI: point, 00, minus, dollar sign?
TEACHER: You don't need another dollar sign. You just need one at the beginning.
ALI: Dollar sign, do I need a number sign?
TEACHER: No, you do not need another number sign.
Audio Description: Ali reads what she has already written.
ALI: minus, 161
TEACHER: It's a good thing we're writing it down because you almost forgot it, didn't you? Okay, now space over and put your equals sign.
[sound of braillewriter]
Did you write this problem going vertically, up and down, or horizontally, going left and right?
ALI: Horizontally
TEACHER: Can you write math problems vertically?
ALI: Yep.
TEACHER: How do print people write math problems? Like your teachers, and your Mom and Dad, do we write them going the same way you do?
ALI: No.
TEACHER: How do we write them? Do you remember, we discussed this one day?.
ALI: Carrying over.
TEACHER: We do carrying. Is it written left to right or is it written top to bottom, up and down?.
ALI: left to right.
TEACHER: No, print people work up and down. We go up and down. And you've seen them written that way and we're going to practice writing it that way also.
ALI: Oh no.
TEACHER: Ohhh, I know it's horrible, isn't it? Okay, what we need to do is we need to check our problem on the Abacus and I'm going to scoot over so that I can be close to you.
Audio Description: Both the teacher and Ali have an abacus.
TEACHER: Okay, what is the subtraction problem?
ALI: 2 dollars minus 161
TEACHER: Oh, there's that chatty Barbie voice. Okay, let's check this on our Abacus. Okay?
ALI: 2 dollars...
TEACHER: Or we're going to think about it as 200, because I have not shown you money on this yet. Okay, minus what?
ALI: 161
TEACHER: Nice and loud, this is...
ALI: 100
ALI: minus 60, don't have 60
TEACHER: So what do we do?
ALI: minus a 10
TEACHER: Okay
ALI: We don't have a 10.
TEACHER: But we have a what?
ALI: a hundred
TEACHER: Okay, but we wanted to subtract what?
ALI: 60
TEACHER: Okay, is a hundred too much?
ALI: Yep
TEACHER: How much?
ALI: 40
TEACHER: 40, so what do we do in that tens column?
ALI: Add 40.
TEACHER: Correct. Okay, now what do we need to subtract from our ones column?
ALI: 1, don't have 1, so I do to my..., subtract a 10 and add 9
TEACHER: Oh, there's that chatty Barbie I was looking for. Okay, what did you get?
Audio Description: Ali checks her answer on the abacus.
ALI: 39
TEACHER: Is that what we got before?
ALI: Yep
TEACHER: Alright, now just to double, double, triple check, I'm going to have you check it on the calculator, which is over to your left. This is the same one we've worked on before and I believe this is the one you have at home.
ALI: It is. Okay.
TEACHER: If you can't remember your problem, better look on your braillewriter.
Audio Description: Ali checks the problem in the braillewriter.
ALI: 2 point 00
CALCULATOR: 2 point 00, minus minus 1 61
Audio Description: Ali, again, checks the problem in the braillewriter.
TEACHER: Don't forget your decimal point. Okay?
ALI: I forgot the decimal point.
TEACHER: No you didn't, when you put it in. You did it right the first time.
ALI: No, when I wrote it.
TEACHER: Oh, when you wrote it, okay, I'll forgive you, that's okay.
CALCULATOR: point 6 1 equals 0 point 3 9
ALI: I got it right.
TEACHER: Oh, you're so smart. Give me five.