Tell me, why is common core a thing? http://www.businessins

>>7674137
I am generally against common core but have no problem with this one. Commutativity is important to learn.

>>7674148
But at least on the first problem there is nothing about commutativity. In this case, the numbers commute so you could do that repeated addition operation in any way you want.

Spoken those two problems say 5 groups of 3 and 4 groups of 6.

>>7674148
I have to disagree. I grew up with the idea that commutativity always applies and had no problems. Now I'm in Linear Algebra, where the order of multiplication does matter. The transition was not a problem.

When I started learning multiplication, I would have said 5 x 3 as "five three times" in my head because that's how it made sense to me. Maybe I'm retarded, but I always figured out the maths questions faster than any other kid in my class.

>>7674137
Tell me, what does your pic have to do with common core? Common core is not a curriculum, it is a set of educational standards. It does not mandate particular ways of teaching addition.

>>7674158
You're not retarded but matrix multiplication the order does matter and you're thinking about it the wrong way. And your definition of multiplication uses the word in the definition which is why it's better to think of it this way >>7674153

>>7674155
Yeah, we should just teach math to kids without any particular goal in mind. Getting them ready for lower-division university math is the only thing that matters, certainly not fostering different patterns of abstract reasoning that will help them in a wide range of contexts and promote more logically responsible public life and society

Waaah I didn't get introduced to the basic principles of multiplication by a scalar before I was told * commutes on R so it's an objectively incorrect approach

>>7674137

1900 BC (Egyptian, Moscow Papyrus): If someone brings in 100 logs measuring 2 by 2, then how many logs measuring 5 by 1 does this correspond to?

1900: A logger sells a truckload of lumber for $100. His cost of production is 4/5 of this price. What is his profit?

1920 (Progressive reform): Math "is a nonfunctional and nearly valueless subject"

1960 (New math): A logger sells a truckload of lumber for $144 (base 8). His cost of production is 0.4 (base 5) of this price. What is his profit in base 10?

1970 ("Traditional" math): A logger sells a truckload of lumber for $100. His cost of production is $80. What is his profit?

1980 (New-New math): A logger exchanges a set L of lumber for a set M of money. The cardinality of set M is 100 and each element is worth $1.

(a) make 100 dots representing the elements of the set M

(b) The set C representing costs of production contains 20 fewer points than set M. Represent the set C as a subset of the set M

(c) What is the cardinality of the set P of profits?

1990 (Calculator enhanced math): Type the number "100". Hit the minus, "-", key. Now type "80" and hit the equals key which looks like "=" or "↲". Does everyone see the number "20"?

1995 (Dumbed-down math): A logger sells a truckload of lumber for $100. His cost of production is $80 and his profit is $20. Underline the number 20.

2012 (Common Core Math™): By cutting down a forest full of beautiful trees, a logger makes $20.

(a) What do you think of this way of making money?

(b) How did the forest birds and squirrels feel?

(c) Draw a picture of the forest as you'd like it to look.

Home schooling (Real math): Logging Company sells some logs for $100. The company had to pay 19% of the sale for the taxes. 18% of the gross has to be used for stock dividend pay outs and an extra 11% of the total goes toward liability insurance. 7% of the sale needs to pay for employee wages and then 25% of the transaction gets sucked away by the mob. What's the bottom line?

>>7674234
>ending with homeschool
>toptroll mate.

>>7674234
old and unfunny. 0/10

>>7674244

I didn't know about the quote that mathematics is "nonfunctional and nearly valueless" which is actually a real quote from 1920s educators (but with Algebra instead of math since people obviously use arithmetics when running a shop). Most versions of the joke start at the 1950s with the 1900 problem.

>>7674257
Put pearls on shit and it's still shit.

>>7674234
That joke was funnier when Tom Lehrer told it
https://www.youtube.com/watch?v=UIKGV2cTgqA