Subtract 36/20 from 72/42
1st number: 1 30/42, 2nd number: 1 16/20
72/42 - 36/20 is -3/35.
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,
36/20 = 36 × 21/20 × 21 = 756/420 - Subtract the two like fractions:
720/420 - 756/420 = 720 - 756/420 = -36/420 - After reducing the fraction, the answer is -3/35
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