Subtract 72/20 from 21/7
1st number: 3 0/7, 2nd number: 3 12/20
21/7 - 72/20 is -3/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 7 × 20 = 140,
21/7 = 21 × 20/7 × 20 = 420/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
72/20 = 72 × 7/20 × 7 = 504/140 - Subtract the two like fractions:
420/140 - 504/140 = 420 - 504/140 = -84/140 - After reducing the fraction, the answer is -3/5
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