Subtract 20/21 from 42/75
42/75 - 20/21 is -206/525.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 21 is 525
Next, find the equivalent fraction of both fractional numbers with denominator 525 - For the 1st fraction, since 75 × 7 = 525,
42/75 = 42 × 7/75 × 7 = 294/525 - Likewise, for the 2nd fraction, since 21 × 25 = 525,
20/21 = 20 × 25/21 × 25 = 500/525 - Subtract the two like fractions:
294/525 - 500/525 = 294 - 500/525 = -206/525
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