You have a bar of chocolate made up of 60 squares in a 10 x 6 arrangement.

You need to split it into individual squares in the least possible amount of cuts.

You are allowed to employ straight cuts or zig-zag cuts but you can't put one piece on top of another and cut both at the same time.

As soon as you get an individual square you are allowed to eat it so there is an incentive to get individual squares sooner rather than later.

Adopting best strategy, what is the minimum number of cuts needed?

Could you explain "zig-zag cuts"?
Like, starting top left going "down-right" (5 times) ending with "down" counts as 1 cut?

Correct. That is one cut.

Hmmm...I presume that (so not to "lift" the knife
thus terminating a cut) I can't move the knife if
no actual cutting is being made; like, I can't
move the knife anywhere on the "outside"...I'll
assume I can't do that...

I can start at top left, under the corner square,
go right-down-right-up-right-down....until a final
"down" one square from right edge, then:
left-down-left-up...until final "left" one square
from left edge; at this point, I've cut loose and
eaten 7 little squares;
I can continue (still considered 1st cut) similarly
until I'm at bottom left corner:
so I've now eaten 21 or 22 li'l squares (depending
on how I end 1st cut) : hoping you can follow that, I ask : agree?!!

As usual, Denis your creativity and imagination astound me.
Now I realize that I should have done a better job of defining a cut.
The intention is that a cut ends when the piece of chocolate you are cutting on that turn is in more than one piece.

So, in your example,

"I can start at top left, under the corner square,
go right-down-right-up-right-down....until a final
"down" one square from right edge, then:
left". That's where the cut ends because you now have two pieces of chocolate.

Hope that's clear.

Sorry for the confusion.

> The intention is that a cut ends when the piece of chocolate you are
> cutting on that turn is in more than one piece.

So 3 cuts required to cut in quarters?
1 along middle line; but 2 for other middle line?
Yikes!!

Correct. You can only cut one piece at a time.

Interesting observation. Many math professors have apparently struggled with this for several hours/days.

Most first graders figure it out in a few minutes.

The only reason I'm even replying is due to the fact you said 'Most first graders figure it out in a few minutes' (that's my level of mathemathics).

I've tried this with smaller bars of chocolate i.e 4 squares in total, answer: 3 cuts, 10 squares in total, answer: 9 cuts. By that logic (and I use the term loosely), 60 squares, answer : 59 cuts????

Exactly, Treval!

Here's the point. You can only cut one piece at a time so, after a cut, you have one more piece than you did before.

After one cut you have 2 pieces
After two cuts you have 3 peices
After three cuts you have 4 pieces
..........
After n cuts you have n+1 pieces


So all cutting strategies are the same. To cut a 60 piece block into individual squares you need 59 cuts. Whether you choose zig-zags or straight cuts is irrelevant.