The sum of the numerator and denominator of a proper fraction is 25. If the numerator is decreased by 1, then the ratio of the new numerator to denominator is 1:2. Determine the original fraction. Show working
original fraction:
n + d = 25
new fraction:
(n-1) : d = 1:2
2n-2 = d
2n - d = 2
add the two equations,
3n = 27
n = 9 and d = 16
the fraction was 9/16