Subtract 72/30 from 20/21
1st number: 20/21, 2nd number: 2 12/30
20/21 - 72/30 is -152/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
20/21 = 20 × 10/21 × 10 = 200/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
72/30 = 72 × 7/30 × 7 = 504/210 - Subtract the two like fractions:
200/210 - 504/210 = 200 - 504/210 = -304/210 - After reducing the fraction, the answer is -152/105
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