Subtract 70/18 from 81/72
1st number: 1 9/72, 2nd number: 3 16/18
81/72 - 70/18 is -199/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 18 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 72 × 1 = 72,
81/72 = 81 × 1/72 × 1 = 81/72 - Likewise, for the 2nd fraction, since 18 × 4 = 72,
70/18 = 70 × 4/18 × 4 = 280/72 - Subtract the two like fractions:
81/72 - 280/72 = 81 - 280/72 = -199/72
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