Subtract 84/20 from 72/42
1st number: 1 30/42, 2nd number: 4 4/20
72/42 - 84/20 is -87/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 42 × 10 = 420,
72/42 = 72 × 10/42 × 10 = 720/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
84/20 = 84 × 21/20 × 21 = 1764/420 - Subtract the two like fractions:
720/420 - 1764/420 = 720 - 1764/420 = -1044/420 - After reducing the fraction, the answer is -87/35
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