Subtract 20/15 from 21/4
1st number: 5 1/4, 2nd number: 1 5/15
21/4 - 20/15 is 47/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 15 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 4 × 15 = 60,
21/4 = 21 × 15/4 × 15 = 315/60 - Likewise, for the 2nd fraction, since 15 × 4 = 60,
20/15 = 20 × 4/15 × 4 = 80/60 - Subtract the two like fractions:
315/60 - 80/60 = 315 - 80/60 = 235/60 - After reducing the fraction, the answer is 47/12
- In mixed form: 311/12
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