Henry Dudeney was an English mathematician who specialized in logic puzzles and mathematical games.   Here is one of his puzzles:
The challenge is to get the numbers 1 through 9, in order, to form an expression that equals 100, using only basic arithmetic operations (+, -, x, /) and parentheses.   For example:
1 + 2 + 3 + 4 + 5 + 6 + 7 + (8 x 9) = 100

Can you find another solution that uses just three operations and no parentheses?




Solution to the Problem:

123 - 45 - 67 + 89 = 100

Besides sending in the solution above, Vikash Kumar sent in the following solution which used just three operators (-,+,*):
-1*2-3+4*5+6+7+8*9 = 100
William Vargo also sent in the solution 1*2+3*4-5*6-7+8+9=100 with three operators. (*, -, +).
Then James Alarie sent in the following, so he gets extra credit for this month!!
He found 101 answers without parenthesis and only one with exactly three operators:

Three operators: 123-45-67+89.

Full list:
123+45-67+8-9
123+4-5+67-89
123+4*5-6*7+8-9
123-45-67+89
123-4-5-6-7+8-9
12+34+5*6+7+8+9
12+34-5+6*7+8+9
12+34-5-6+7*8+9
12+34-5-6-7+8*9
12+3+4+5-6-7+89
12+3+4-56/7+89
12+3-4+5+67+8+9
12+3*45+6*7-89
12+3*4+5+6+7*8+9
12+3*4+5+6-7+8*9
12+3*4-5-6+78+9
12-3+4*5+6+7*8+9
12-3+4*5+6-7+8*9
12-3-4+5-6+7+89
12-3-4+5*6+7*8+9
12-3-4+5*6-7+8*9
12*3-4+5-6+78-9
12*3-4-5-6+7+8*9
12*3-4*5+67+8+9
12/3+4*5-6-7+89
12/3+4*5*6-7-8-9
12/3+4*5*6*7/8-9
12/3/4+5*6+78-9
1+234-56-7-8*9
1+234*5*6/78+9
1+234*5/6-7-89
1+23-4+56+7+8+9
1+23-4+56/7+8*9
1+23-4+5+6+78-9
1+23-4-5+6+7+8*9
1+23*4+56/7+8-9
1+23*4+5-6+7-8+9
1+23*4-5+6+7+8-9
1+2+34-5+67-8+9
1+2+34*5+6-7-8*9
1+2+3+4+5+6+7+8*9
1+2+3-45+67+8*9
1+2+3-4+5+6+78+9
1+2+3-4*5+6*7+8*9
1+2+3*4-5-6+7+89
1+2+3*4*56/7-8+9
1+2+3*4*5/6+78+9
1+2-3*4+5*6+7+8*9
1+2-3*4-5+6*7+8*9
1+2*34-56+78+9
1+2*3+4+5+67+8+9
1+2*3+4*5-6+7+8*9
1+2*3-4+56/7+89
1+2*3-4-5+6+7+89
1+2*3*4*5/6+7+8*9
1-23+4*5+6+7+89
1-23-4+5*6+7+89
1-23-4-5+6*7+89
1-2+3+45+6+7*8-9
1-2+3*4+5+67+8+9
1-2+3*4*5+6*7+8-9
1-2+3*4*5-6+7*8-9
1-2-34+56+7+8*9
1-2-3+45+6*7+8+9
1-2-3+45-6+7*8+9
1-2-3+45-6-7+8*9
1-2-3+4*56/7+8*9
1-2-3+4*5+67+8+9
1-2*3+4*5+6+7+8*9
1-2*3-4+5*6+7+8*9
1-2*3-4-5+6*7+8*9
1*234+5-67-8*9
1*23+4+56/7*8+9
1*23+4+5+67-8+9
1*23-4+5-6-7+89
1*23-4-56/7+89
1*23*4-56/7/8+9
1*2+34+56+7-8+9
1*2+34+5+6*7+8+9
1*2+34+5-6+7*8+9
1*2+34+5-6-7+8*9
1*2+34-56/7+8*9
1*2+3+45+67-8-9
1*2+3+4*5+6+78-9
1*2+3-4+5*6+78-9
1*2+3*4+5-6+78+9
1*2-3+4+56/7+89
1*2-3+4-5+6+7+89
1*2-3+4*5-6+78+9
1*2*34+56-7-8-9
1*2*3+4+5+6+7+8*9
1*2*3-45+67+8*9
1*2*3-4+5+6+78+9
1*2*3-4*5+6*7+8*9
1*2*3*4+5+6+7*8+9
1*2*3*4+5+6-7+8*9
1*2*3*4-5-6+78+9
1*2/3+4*5/6+7+89
1/2*34-5+6-7+89
1/2*3/4*56+7+8*9
1/2/3*456+7+8+9


Correctly solved by:

1. Vikash Kumar New Delhi, India
2. William Vargo Calgary, Alberta, Canada
3. Sascha Moline Calgary, Alberta, Canada
4. James Alarie Flint, Michigan