Posted on 03/21/2014 11:13:57 PM PDT by chessplayer
College students and others at George Mason University were dumbstruck by the tedious nature of an elementary level Common Core problem during a short series of interviews conducted by Campus Reform last week. The problem, 32-12, was demonstrated to those on campus the traditional way and juxtaposed with the Common Core method.
(Excerpt) Read more at conservativevideos.com ...
where did they get the 3 from in the first line?
all that to avoid simple subtraction??
they’re doing everything they can to undermine education in this country. the result will be more people in need of govt assistance.... more people on food stamps and welfare... more people voting for democrats to insure they get it
just remember, democrats gain voters as more people end up on welfare and food stamps.
I don’t get any of it ...
I get the 12, where do you get the 3 to make 15
Assuming 15 is right, where do you get the 5 to make 20
Assuming 20 is right, where do you get the 10 to make 30
Assuming 30 is right, where do you get the 2 to make 32
Or any of the other numbers that aren’t 32 and 12?
Here’s the thing, we all already do this kind of math each and every day. Knowing how to do this is quite useful.
Let’s make the problem a bit more likely, though.
I go to the hardware store to buy something that is $12. I have a $10 and a $20 bill, so I give the person at the checkout counter $30. This person now has to make change.
The teller grabs 3 $1 bills and puts them on the counter, and says, “12 + 3 is 15”.
The teller then grabs a $5 bill and puts it on the counter, and says, “and 5 makes 20.”
The teller then grabs a $10 bill and puts it on the counter, and says, “and 10 makes 30.”
The item is $12. I put down $30. The teller counted out $3 + $5 + $10, or $18 in change. WHICH IS THE CORRECT ANSWER. This is a real life example of what happens in hardware stores across the country each and every day.
Just because you do not understand what is being taught does not mean that what is being taught is useless, confusing, or pointless. I am NOT defending common core. What I am defending is teaching children how to do the same kind of real-world practical math that we do every day.
That not how I do math
All there are doing is adding to 12 to get to 32. Guess they figure our kids are to stupid to subtract or our teachers are to stupid to teach subtraction so they just teach addition. How much do I have to add to 12 to get to 32 is the same as 32 minus 12.
30
-12
= 18
So much simpler and faster
That is cumbersome and stupid
Let's make the problem what actually happens. I go to the hardware store to buy something for $12. The clerk scans it, I hand her a credit card, and the register spits out a receipt.
The process you're describing was automatic for us before the advent of technology because we were drilled in fundamentals, and knew the addend or subtrahend of any two numbers since second grade, cold.
When you concentrate on conceptual mathematics to children who don't reflexively know the basics, you are wasting your time, just as you have wasted your time with a contrived example.
If you give the teller a ten and a twenty for a twelve dollar item if are either having a very bad day or you are an idiot.
The teller grabs 3 $1 bills and puts them on the counter, and says, “12 + 3 is 15”.
The teller then grabs a $5 bill and puts it on the counter, and says, “and 5 makes 20.”
Umm. Its only $12 for the purchase. I'd only be giving the $20 in the first place. So, it would be 12+3+5 but this is too complicated.
Without using traditional subtraction:
20 is a decimal count, 2 units of 10. 12 is a decimal count of 1 unit of ten and 2 units of 1. There are 8 units of one between the decimal counts.
8 is the correct answer. The teller has a fiver and 3 ones, that is the change.
QED.
Lol
If the item cost $12 and you have a $20 and a $10 why would you give the cashier $30? Since there is no $30 bill? I don’t know maybe they do things different in your part of the world.
Because they use common core math so they give the extra money so the cashier can give the correct change.
LOL!
“If you give the teller a ten and a twenty for a twelve dollar item if are either having a very bad day or you are an idiot.”
He’s an idiot.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.