Subtract 72/21 from 42/14
1st number: 3 0/14, 2nd number: 3 9/21
42/14 - 72/21 is -3/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 14 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 14 × 3 = 42,
42/14 = 42 × 3/14 × 3 = 126/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
72/21 = 72 × 2/21 × 2 = 144/42 - Subtract the two like fractions:
126/42 - 144/42 = 126 - 144/42 = -18/42 - After reducing the fraction, the answer is -3/7
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