Using the digits 1 to 9 in order and only + or − signs, can you make 100?
Hint: Some digits can be joined into bigger numbers.
1 + 2 + 3 − 4 + 5 + 6 + 78 + 9 = 100 (one of several answers).
Joining digits into numbers like 78 gives you enough range. Other solutions include 123 − 45 − 67 + 89 = 100.
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