If we're dealing only with positive quantities:
If the numerator of a fraction is larger than the denominator, and you add 30 to both, the value of the fraction goes down:
10/3 is greater than 40/33, for example
If the numerator is smaller than the denominator, and you add 30 to both, the value of the fraction goes up:
1/2 is less than 31/32, for example
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