97, for example.
34
13 = 7 + s(13 - 7) = (7-7) + s6 = s
The answer will depend on what kind of sums.
There are 22 sums, if you don't include a number more than once. Where did you here a question like that?
All the possible sums are: 6 7 8 9 11 12 13 16 17 21
350/7=50
0+7=71+6=72+5=7 3+4=7
No.
97, for example.
the magic sums are 15, 34, and42
34
13(13) into 0(7) dump 7 6(13) into 0(7) fill 13 13(13) into 6(7) dump 7 12(13) into 0(7) dump 7 5(13) into 7 fill 13 13(13) into 5(7) dump 7 11(13) into 0(7) dump 7 4(13) into 0(7) fill 13 13(13) into 4(7) left with 10/13 7(7) into 0(19) fill 7 7(7) into 7(19) fill 7 7(7) into 14(19) 19(19) into 5(7) dump 7 17(19) into 0(7) left with 10(19)
7/13 is already in simplest form.
The reciprocal of -13/7 is -7/13
magic box 1 is 15
1