Subtract 42/21 from 7/72
1st number: 7/72, 2nd number: 2 0/21
7/72 - 42/21 is -137/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
7/72 = 7 × 7/72 × 7 = 49/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
42/21 = 42 × 24/21 × 24 = 1008/504 - Subtract the two like fractions:
49/504 - 1008/504 = 49 - 1008/504 = -959/504 - After reducing the fraction, the answer is -137/72
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