Answer:
Step-by-step explanation:
Each of the equations represents equivalent fractions except the one in choice C.
13/20 = 26/40, not 25/40.
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<em>Comment on equal sign</em>
IMO, one should never use an equal sign where things are not equal--unless there is a clear indication you understand they are not equal. The equal sign should be regarded as a sacred symbol, with very specific rules as to its meaning and use.