Subtract 21/42 from 35/72
35/72 - 21/42 is -1/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 42 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
35/72 = 35 × 7/72 × 7 = 245/504 - Likewise, for the 2nd fraction, since 42 × 12 = 504,
21/42 = 21 × 12/42 × 12 = 252/504 - Subtract the two like fractions:
245/504 - 252/504 = 245 - 252/504 = -7/504 - After reducing the fraction, the answer is -1/72
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