Anonymous
Post 02/07/2020 12:28     Subject: Math problem - what's your answer?
Anonymous wrote:
Anonymous wrote:20 min = 5 pieces
X min = 10 pieces

40.

Takes him 2x as long for 2x the amount.


OP here. This was my first thought, and my kid's. But everyone who said 45 minutes is in fact correct. 5 minutes per chop and 9 chops to get 10 pieces.


Wait a second now. You said "cut" before, which implies use of a saw. Now he's chopping? That's a whole other equation.



/s
Anonymous
Post 02/07/2020 12:25     Subject: Math problem - what's your answer?
Of course, the saw blade gets dull by about the 10th cut and takes 10 minutes to sharpen. Must account for that.
Anonymous
Post 02/07/2020 12:14     Subject: Math problem - what's your answer?
Anonymous wrote:Double the work, double the time.


Except the work did not double. It increase by 125%.
Anonymous
Post 02/07/2020 12:02     Subject: Math problem - what's your answer?
Double the work, double the time.
Anonymous
Post 02/07/2020 11:52     Subject: Math problem - what's your answer?
Anonymous wrote:
Anonymous wrote:
Anonymous wrote:
Anonymous wrote:I wonder of this is why I did miserably on the math SATs.

I can see why either 40 or 45 would be the right answer.


Explain how 40 could be the right answer?


Posted up thread, but 2x as long to do 2x as much work. 40 min.

Interesting how some people were focused on how many "cuts" while others saw it as production.



But it's not two times as much work. The work is the cutting. It's four cuts to get five pieces, and nine cuts to get 10 pieces. If the question was about carving something out of existing wood pieces, then it would be twice as much work to do twice as many pieces.


Well, she did say she did miserably on SAT.
Anonymous
Post 02/07/2020 08:50     Subject: Math problem - what's your answer?
Anonymous wrote:
Anonymous wrote:
Anonymous wrote:20 min = 5 pieces
X min = 10 pieces

40.

Takes him 2x as long for 2x the amount.


OP here. This was my first thought, and my kid's. But everyone who said 45 minutes is in fact correct. 5 minutes per chop and 9 chops to get 10 pieces.


You cut 4 times to make 5 pieces, you don't cut 5 times. Are you fighting this? Because if you are, you're wrong.


Not fighting it at all. Just wondering if everyone/anyone else's first thought was 40. If one thing takes 20 minutes, 2x that thing takes 40 minutes. But for CML that's clearly too simple.

Apparently I'm the dumb one I used to be super good at math but I guess my mind doesn't work that way anymore.
Anonymous
Post 02/07/2020 08:09     Subject: Math problem - what's your answer?
He is using druzhba and 9 cuts is not tiring at all. We are not talking about 900 cuts.
If the kids are so smart, why not write 45, which is what they are asking and then go on and on writing whatever the kids want to write and the comments they want to make.
Anonymous
Post 02/07/2020 07:53     Subject: Math problem - what's your answer?
Anonymous wrote:
Anonymous wrote:
Anonymous wrote:
Anonymous wrote:I wonder of this is why I did miserably on the math SATs.

I can see why either 40 or 45 would be the right answer.


Explain how 40 could be the right answer?


Posted up thread, but 2x as long to do 2x as much work. 40 min.

Interesting how some people were focused on how many "cuts" while others saw it as production.



But it's not two times as much work. The work is the cutting. It's four cuts to get five pieces, and nine cuts to get 10 pieces. If the question was about carving something out of existing wood pieces, then it would be twice as much work to do twice as many pieces.


Not if he's using a hand saw. That gets really tiring. And you get blisters, so that slows it down too.
Anonymous
Post 02/07/2020 07:52     Subject: Math problem - what's your answer?
Anonymous wrote:
Anonymous wrote:You might want to factor in how tired Mr. Sawyer gets. The rate of work slows down as production increases.


That’s exactly how my brain looked at it. Unfortunately too many people look at people as machines, so there’s little to no fatigue factored into planning.


My kids think this way too. I have to tell them, now go into the imaginary world of people who write these test questions without really thinking about situation, and just do the simple math. They want the simple answer.
Anonymous
Post 02/07/2020 07:51     Subject: Math problem - what's your answer?
Anonymous wrote:
Anonymous wrote:
Anonymous wrote:I wonder of this is why I did miserably on the math SATs.

I can see why either 40 or 45 would be the right answer.


Explain how 40 could be the right answer?


Posted up thread, but 2x as long to do 2x as much work. 40 min.

Interesting how some people were focused on how many "cuts" while others saw it as production.



But it's not two times as much work. The work is the cutting. It's four cuts to get five pieces, and nine cuts to get 10 pieces. If the question was about carving something out of existing wood pieces, then it would be twice as much work to do twice as many pieces.
Anonymous
Post 02/07/2020 07:49     Subject: Math problem - what's your answer?
Anonymous wrote:
Anonymous wrote:
Anonymous wrote:My kids answered: It depends. Is he in shape? Does he need a break to do more cuts? Is it the same size log and if so is it more difficult to cut it into smaller pieces versus larger pieces? And if it isn't the same size log, does it take longer to manipulate the larger log in the first place?

Sigh. Maybe this kid will get better grades in physics some day? Or become a lawyer.


This is exactly how I was answering it too. I overanalyze everything and wouldn't have even thought of this as a math problem in the first place.


Those are not remotely good answers to a CML. The answer line is a small little line.


CML?
Anonymous
Post 02/07/2020 07:42     Subject: Math problem - what's your answer?
On a side note - I was one of those people who heard "Yanny" and my first thought was 40.

For those who answered 45. Did you hear "Laurel"?


Anonymous
Post 02/07/2020 07:39     Subject: Math problem - what's your answer?
Anonymous wrote:
Anonymous wrote:I wonder of this is why I did miserably on the math SATs.

I can see why either 40 or 45 would be the right answer.


Explain how 40 could be the right answer?


Posted up thread, but 2x as long to do 2x as much work. 40 min.

Interesting how some people were focused on how many "cuts" while others saw it as production.

Anonymous
Post 02/07/2020 03:03     Subject: Math problem - what's your answer?
Anonymous wrote:
Anonymous wrote:
Anonymous wrote:
Anonymous wrote:You might want to factor in how tired Mr. Sawyer gets. The rate of work slows down as production increases.


On the other hand, he's dealing with lighter pieces so it might be easier.

Honestly, I feel like 17 of those 20 minutes are going to be putting gas in the chainsaw, and getting it out of the garage in the first place.


I don't know, after he realized he cut the first ones wrong he's getting kind of stressed and sweaty and pretty soon he's going to saw off a finger.

Even worse--after all that he will realize he needed 11 psots, not 10, to put a post every 10 feet on a 100 foot stretch of yard by the driveway and he's going to have to cut down another tree.


So, if you have to visit the ER, and get emergency surgery, and then recuperate before you try, do you add the whole time to the total?

"If cutting a log into 10 pieces of wood took 2 months, 3 hours and $6,200 plus lost wages, what was the time and cost to chop a log into 15 pieces?"


Ha Ha! Hilarious! And rather realistic as to how this would probably transpire at my house.
Anonymous
Post 02/07/2020 01:00     Subject: Re:Math problem - what's your answer?
45 mins is the obvious answer.

If it's a computer science class or similar then that would be different, but I guess then you wouldn't be posting in the elementary section.

- mathematician