Question

A carpenter got given some free wooden planks. Some are 12m long and some are 18m long. She wants to cut them up so that she has equal size planks to make using them easier. What size planks should she cut them into to avoid wasting any wood?

Answer 1

12 = 2*6
18 = 3*6

of course she could cut them into 2 or 3 foot lengths, but for min waste use the biggest common factor

Answer 2

I would say 12m because you can't cut a 12m plank into something like a 16 meter plank but you can cut a 18m plank shorter to make it 12m long.

Answer 3

This question makes very little sense to me.

I suppose they are after a length of 6 m, since 12/6 and 18/6 are whole numbers
(but so would length of 3 m)
But the length of a board does not have anything to do with whole numbers,
e.g. a board of length 6.5 m is just as good a board as one of 6 m.
Why not keep the boards as they are and cut them as needed?

Furthermore the question avoids the real situation of loss of wood due to the saw cut.
Lastly, what the heck does "got given" mean ?

Answer 4

so you waste all the six footers?

Answer 5

LOL, carpenters want the max that fits on the truck for min waste on the site.