This sum is more difficult than any other

[Ador]

What are the differences between these sentences -

1. This sum is more difficult than any other sum in this book.

2. This sum is more difficult than all other sum in this book.

 

[Ador]

The first is OK. The second isn't. It would be OK if you made 'sum' plural.

It would be better if you explain to me their uses. I mean when to use "all other" and "any other" in comparing something.

 

[Tarheel]

Are those your sentences?

How can a sum be difficult?

 

[GoesStation]

How can a sum be difficult?

In British English, "sum" can mean "arithmetic problem". Learners should note that we don't use the word that way in American English.

 

[Tarheel]

In American English the sum of 3 plus 4 is 7.

 

[Ador]

In American English the sum of 3 plus 4 is 7.

Tarheel, do both of these sentences have same meaning? Are there any differences between "any other" and "all other"?

 

[GoesStation]

"Any other" refers to individual sums ("problems" in American English): there is no single sum in the book that's more difficult than this one.

"All other" refers to every sum: every other sum in the book is easier than this one.

There's little practical difference between them in this case.