Subtract 21/15 from 7/20
1st number: 7/20, 2nd number: 1 6/15
7/20 - 21/15 is -21/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 15 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 20 × 3 = 60,
7/20 = 7 × 3/20 × 3 = 21/60 - Likewise, for the 2nd fraction, since 15 × 4 = 60,
21/15 = 21 × 4/15 × 4 = 84/60 - Subtract the two like fractions:
21/60 - 84/60 = 21 - 84/60 = -63/60 - After reducing the fraction, the answer is -21/20
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