Subtract 63/18 from 81/30
1st number: 2 21/30, 2nd number: 3 9/18
81/30 - 63/18 is -4/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
81/30 = 81 × 3/30 × 3 = 243/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
63/18 = 63 × 5/18 × 5 = 315/90 - Subtract the two like fractions:
243/90 - 315/90 = 243 - 315/90 = -72/90 - After reducing the fraction, the answer is -4/5
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