Subtract 20/21 from 42/60
42/60 - 20/21 is -53/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 60 × 7 = 420,
42/60 = 42 × 7/60 × 7 = 294/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
20/21 = 20 × 20/21 × 20 = 400/420 - Subtract the two like fractions:
294/420 - 400/420 = 294 - 400/420 = -106/420 - After reducing the fraction, the answer is -53/210
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