Open Middle®
Directions: Using the digits 1 to 9, at most one time each, place a digit in each box to find the closest product to 500.
Hint
What numbers could you use to split 500 into equal groups (think about less than 5 groups).
Answer
167 x 3 = 501 is really close and 125 x 4 = 500 is the closest
498 x 1 = 498 is also very close.
Source: Jessica Goree
I can confirm that 125*4, 167*3 and 498*1 are the only solutions that are exactly 0, 1 and 2 away from 500.