between the numbers 1,2,3,4,5,6,7,8,9 put that sign you want and add them in order to give sum 10!
(Each number put only once, and only + ,- .. not *,/)
Can't be done....unless I'm missing something (still on 1st coffee!)
Sum of the 9 digits = 45;
a + b = 45
a - b = 10
========
2a = 55
a = 27.5
Are we allowed to use the likes of 1+23?
1 to 8 works; sum = 36:
a + b = 36
a - b = 10
========
2a = 46
a = 23
So 23 and -13:
1 + 2 + 3 + 4 + 5 - 6 - 7 + 8 = 10
1 + 2 + 3 + 4 - 5 + 6 + 7 - 8 = 10 ....and a few others...