Subtract 63/42 from 81/30
1st number: 2 21/30, 2nd number: 1 21/42
81/30 - 63/42 is 6/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
81/30 = 81 × 7/30 × 7 = 567/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
63/42 = 63 × 5/42 × 5 = 315/210 - Subtract the two like fractions:
567/210 - 315/210 = 567 - 315/210 = 252/210 - After reducing the fraction, the answer is 6/5
- In mixed form: 11/5
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