How many ways to total 21 by using the digits 1 through 11?

Answer 1

40 possible combinations listed below

1+2+3+4+5+6

1+2+3+4+11

1+2+3+5+10

1+2+3+6+9

1+2+3+7+8

1+2+4+10

1+2+5+9

1+2+6+8

1+3+4+5+8

1+3+4+6+7

1+3+6+11

1+3+7+10

1+3+8+9

1+4+5+11

1+4+6+10

1+4+7+9

1+5+6+9

1+5+7+8

1+9+11

2+3+4+5+7

2+3+5+11

2+3+6+10

2+3+7+9

2+4+5+10

2+4+6+9

2+4+7+8

2+5+6+8

2+8+11

2+9+10

3+4+5+9

3+4+6+8

3+5+6+7

3+8+10

4+6+11

4+7+10

4+8+9

5+6+10

5+7+9

6+7+8

10+11