Of the following fractions: 9/19, 5/11, 7/15, and 11/23, which is the largest?

Answer 1

Note that each fraction is of the form

n/(2n+1)

This can be written as

1/2 - 1/(2(2n+1))

clearly, as n gets larger, a smaller amount is subtracted, so the fraction with the largest denominator is the largest -- closer to 1/2

Answer 2

1/19 2/19 3/19 7/19. 10/19 11/19