Directions: Using the digits 1 to 9 at most one time each, place a digit in each box to find the largest/smallest possible sum of the three terms in this finite geometric series?

### Hint

How do you generate the terms of a geometric series?

### Answer

The largest possible sum we found was 73 (1 + 8 + 64). The smallest possible sum we found was 21 (3 + 6 + 12).

Source: Dana Harrington