Arrange the numerals 1, 2, 3, 4, 5, 6, 7, 8 and 9, in a single fraction that equals exactly 1/3. For example (which don't work), 1234/56789 = 0.0217.
Probably not, just guess-and-check. (Or, use Google search. )
This reminds me of a problem that was given to our math class in 4th grade. Find a 3-digit number n such that n, 2n and 3n use the digits 1 to 9 exactly once. I was the first to get an answer, which was 327, 654, and 981. I recently found out that this was not the only answer, however. There are three other possible values for n. Can you find them (without using Google )?
01
5823 / 17469 = 1/3
Examples of others:
1/2: 6729 / 13458
1/4: 3942 / 15768
1/5: 2697 / 13485
1/6: 2943 / 17658
1/7: 2394 / 16758
1/8: 3187 / 25496
1/9: 6381 / 57429
No formula.
Shortcuts:
1: find 5digit number = 3 times 4digit number (easier than dividing)
2: both numbers must be either odd or even