Directions: Using the digits 1 to 9 at most one time each, place a digit in each box to make the product as close to 1,000 as possible.
Have you noticed any patterns in your products? Have you tried keeping one factor the same and adjusting your other factor? Are your factors close together? What digits have you tried in the tens place? Can you fine-tune based on your results?
There are several answers that are close. Solutions include: 59×17 = 1,003, 12 x 83 = 996, and 15 x 67 = 1,005.
Source: Ellen Metzger
15×67 wouldn’t work because the answer is 1,005 which uses number 5 twice.