What is possible range of m-n, if -4<m<8 an 1<n<2?

[viccal]

If -4<m<8 and 1<n<2, what is the possible range of m-n?

My answer is -5<m-n<6, but, again, according to the book, it is -6<m-n<7. What's the solution?

Thank you!

[maggiemagnet]

If -4<m<8 and 1<n<2, what is the possible range of m-n?

What are the furthest-apart numbers, both positive and negative, that "m-n" could stand for? Yes, if m=-4 and n=1, then m-n=-5. But what if m=-4 and n=2? Then m-n=-6. Now look at the other end. Yes, if m=8 and n=2, then m-n=6. But what other options are there for m and n? Look at all of the options!