Subtract 21/4 from 21/30
1st number: 21/30, 2nd number: 5 1/4
21/30 - 21/4 is -91/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 4 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 30 × 2 = 60,
21/30 = 21 × 2/30 × 2 = 42/60 - Likewise, for the 2nd fraction, since 4 × 15 = 60,
21/4 = 21 × 15/4 × 15 = 315/60 - Subtract the two like fractions:
42/60 - 315/60 = 42 - 315/60 = -273/60 - After reducing the fraction, the answer is -91/20
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