The product of numerator and denominator of a simplest true fraction is 12. The true fraction is () or ()

The product of numerator and denominator of a simplest true fraction is 12. The true fraction is () or ()

Because it's the simplest fraction
And the numerator × denominator = 12,
1 × 12 = 12
3×4=12
therefore
The product of numerator and denominator of a simplest true fraction is 12, and the true fraction is (1 / 12),
Maybe (3 / 4)

All denominators are the sum of the simplest true fractions of 2009?

2009 is a prime number without any divisor
So the numerator of the simplest fraction with denominator of 2009 is each number from 1 to 2009
1+2+3+...+2009=(1+2009)*2009/2
So the sum of all numbers = (1 + 2009) * 2009 / 2 / 2009 = 1005

All denominators are the sum of the simplest true fractions of 2009, which is equal to ()

The molecules meeting the conditions are 1,2,3,. 2008, excluding the four 2009 factors of 7,41,49287
[（1+2+3+.+2008）-（7+41+49+287）]/2009=2016652/2009

How many are the simplest true fractions with 385 denominator? What is the sum of them

Wengwentao 2009, 385 = 5 × 7 × 11, denominator is the simplest fraction of 385, the multiples of 5, 11 and 7 within 385 can be removed, among which: the multiples of 5: 385 △ 5 = 77; the multiples of 7: 385 △ 7 = 55; the multiples of 11: 385 △ 11 = 35; the multiples of 5 and 7 = 385 △ 35 = 11; at the same time, the multiples of 5 and 7 = 11; at the same time, the multiples of 5 and