Subtract 21/30 from 81/4
1st number: 20 1/4, 2nd number: 21/30
81/4 - 21/30 is 391/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 30 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 4 × 15 = 60,
81/4 = 81 × 15/4 × 15 = 1215/60 - Likewise, for the 2nd fraction, since 30 × 2 = 60,
21/30 = 21 × 2/30 × 2 = 42/60 - Subtract the two like fractions:
1215/60 - 42/60 = 1215 - 42/60 = 1173/60 - After reducing the fraction, the answer is 391/20
- In mixed form: 1911/20
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