hehe - and making it disappear takes zero minutes.

Hi there,

The real problem is that (many) teachers are no longer able to define a problem in such way that "one" only possible answer is correct.

Since no mention to the size and/or shape of the pieces (nor the original board) has been done, the problem has as many valid answers as one could imagine. Even the one propossed by the teacher!! and of course the one given by the alumn... and whatever Marie was able to saw... :-)

No need for the pieces to be of the same size or shape has been declared in the problem text... so: imagine a square board. Saw it into two identical rectangles. (10 min)

Saw one of these rectangles into two squares (5 min)

15 minutes in total, 3 pieces...

Saw the other rectangle into two more squares (5 min)

20 minutes in total, 4 pieces... sure you've got the idea...

Any amount of pieces can be achieved in any amout of time. In fact, the 10 minutes reference in the problem definition is basically useless since Marie could decide to start sawing a tiny corner... and then another one... or this corner into two pieces... or... whatever.

The more obvious is the one proposed by the alumn, three identical pieces from an original rectangle board require two cuts (20 min)

Agreed, this teacher should have the license revoked.

Cheers from the Caribbean Sea.

Diego.

With the picture given the alumn... is definitively "more correct" than the teacher d:-) though I didn't know such a "Kantholz" is called a "board". Consistency is a hard job ... d;-)

Wow, I didn't even notice that drawing on the right!

But certainly this drawing does not show a "board"... may be a "lath".

With this new and valuable info another doubt arises:

Is Marie the right person to run this exercise? (I mean the sawing one)

10 minutes to saw a thin lath!! oh! C'mon!!

;-))

d:-))

Almost like this:

Don't gratuitously complicate and obfuscate the discussion.

It's a board!!!

My father was a math teacher for 32 years. One of my favorite stories is from when he was tutoring someone about decimal numbers and my dad asks them, "What does the decimal point do?"

After a long pause, the student says, "Well... Mr. Dziedzic... it just sits there." qEd!

Here is another:

and another...