Using Up Digits
The sentence 6.5 x 4.321 = 28.0865 has each of the digits 1, 2, 3, 4, 5, and 6 exactly once on the left-hand side. The number on the right-hand side is close to but less than 30. Can you find another multiplication sentence that contains each digit 1, 2, 3, 4, 5, and 6 exactly once on the left side so that the product is even closer to 30 and yet still under 30? How close can you get? Can you find a multiplication sentence with 1, 2, 3, 4, 5, and 6 so that the product is closest to 30 and greater than 30?
(Source: Mathematics Teaching in the Middle School, Nov-Dec 1997)