Directions: Using the digits 1 to 9 exactly one time each, place a digit in each box two times: once to make a sum that is greater than 700 and once to make a sum that is less than 700. You may reuse all the digits for each sum.

### Hint

What place value will be most important to consider? How can you tell whether the sum will be more or less than 700 without adding all of the digits?

### Answer

There are many possible answers, including 129 + 453 for a sum that is less than 700 and 987 + 654 for a sum that is greater than 700.

Source: Robert Kaplinsky

135 + 246 = 381

678 + 954 = 1,632

123 + 456 = 579

486 + 631 = 1117

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John Danthuluri