Subtract 72/20 from 21/14
1st number: 1 7/14, 2nd number: 3 12/20
21/14 - 72/20 is -21/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 14 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 14 × 10 = 140,
21/14 = 21 × 10/14 × 10 = 210/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
72/20 = 72 × 7/20 × 7 = 504/140 - Subtract the two like fractions:
210/140 - 504/140 = 210 - 504/140 = -294/140 - After reducing the fraction, the answer is -21/10
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