Subtract 21/4 from 42/15
1st number: 2 12/15, 2nd number: 5 1/4
42/15 - 21/4 is -49/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 4 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 15 × 4 = 60,
42/15 = 42 × 4/15 × 4 = 168/60 - Likewise, for the 2nd fraction, since 4 × 15 = 60,
21/4 = 21 × 15/4 × 15 = 315/60 - Subtract the two like fractions:
168/60 - 315/60 = 168 - 315/60 = -147/60 - After reducing the fraction, the answer is -49/20
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