Question

6) Use any of the digits 1, 3, and 9 and the operation signs +,- ,x,, to write all the whole numbers from 1 through 13. Each digit can be expressed only once in each example. You can use other digits in the expression, but you must also use a 1, 3, or 9 at least once in each expression.

Answer 1

Explanation:

1 = 1

2 = 3 − 1

3 = 3

4 = 1 + 3

5 = 9 − 3 − 1

6 = 9 − 3

7 = 9 − 3 + 1

8 = 9 − 1

9 = 9

10 = 1 + 9

11 = 9 − 1 + 3

12 = 9 + 3

13 = 1 + 3 + 9