Subtract 81/30 from 21/5
1st number: 4 1/5, 2nd number: 2 21/30
21/5 - 81/30 is 3/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 30 is 30
Next, find the equivalent fraction of both fractional numbers with denominator 30 - For the 1st fraction, since 5 × 6 = 30,
21/5 = 21 × 6/5 × 6 = 126/30 - Likewise, for the 2nd fraction, since 30 × 1 = 30,
81/30 = 81 × 1/30 × 1 = 81/30 - Subtract the two like fractions:
126/30 - 81/30 = 126 - 81/30 = 45/30 - After reducing the fraction, the answer is 3/2
- In mixed form: 11/2
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