Subtract 20/14 from 15/21
1st number: 15/21, 2nd number: 1 6/14
15/21 - 20/14 is -5/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 14 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
15/21 = 15 × 2/21 × 2 = 30/42 - Likewise, for the 2nd fraction, since 14 × 3 = 42,
20/14 = 20 × 3/14 × 3 = 60/42 - Subtract the two like fractions:
30/42 - 60/42 = 30 - 60/42 = -30/42 - After reducing the fraction, the answer is -5/7
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