Subtract 90/63 from 20/72
1st number: 20/72, 2nd number: 1 27/63
20/72 - 90/63 is -145/126.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 63 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 63 × 8 = 504,
90/63 = 90 × 8/63 × 8 = 720/504 - Subtract the two like fractions:
140/504 - 720/504 = 140 - 720/504 = -580/504 - After reducing the fraction, the answer is -145/126
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