Question

Could someone please help me with this?
http://i.imgur.com/vIpgfCR.jpg

Answer 1

In light of the fact that in 26 x 3 = 78, you have only two "small" numbers, focus on those. In other words, you know that if a rearrangement there will work, it MUST be either:

2? x ? = ?? or 3? x ? = ??

since if the 2-digit number start with a 6, 7, or 8, it will result in a 3 digit product. :)

Play around with the digits, see if you can find the one that works there. :)

Answer 2

I don't think that's the one, I think it's 16 x 3 = 48 that will do it. @DebbieG

Answer 3

I was trying to help you find the rearrangement of 26 x 3 = 78 that works.

Since you are trying to determine which one CANT be rearranged, and I think in the work you showed, you had FOUND a successful rearrangement of all but 2 of them, I assumed that you just needed help finding which one of those two COULD be rearranged.

Then, by process of elimination, whatever is left is the one that CANT be rearranged. :)

The only way to truly show that one of them CANT be rearranged would be to try every possible rearrangement... which would be quite unmanageable.

So I agree with you that 16 x 3 = 48 is the answer, the one that can't be rearranged.... because you can show that all of the others, CAN. :)