Subtract 21/7 from 20/72
1st number: 20/72, 2nd number: 3 0/7
20/72 - 21/7 is -49/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 7 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
20/72 = 20 × 7/72 × 7 = 140/504 - Likewise, for the 2nd fraction, since 7 × 72 = 504,
21/7 = 21 × 72/7 × 72 = 1512/504 - Subtract the two like fractions:
140/504 - 1512/504 = 140 - 1512/504 = -1372/504 - After reducing the fraction, the answer is -49/18
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