Subtract 72/20 from 15/84
1st number: 15/84, 2nd number: 3 12/20
15/84 - 72/20 is -479/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
15/84 = 15 × 5/84 × 5 = 75/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
72/20 = 72 × 21/20 × 21 = 1512/420 - Subtract the two like fractions:
75/420 - 1512/420 = 75 - 1512/420 = -1437/420 - After reducing the fraction, the answer is -479/140
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