Subtract 90/72 from 7/9
1st number: 7/9, 2nd number: 1 18/72
7/9 - 90/72 is -17/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 9 × 8 = 72,
7/9 = 7 × 8/9 × 8 = 56/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
90/72 = 90 × 1/72 × 1 = 90/72 - Subtract the two like fractions:
56/72 - 90/72 = 56 - 90/72 = -34/72 - After reducing the fraction, the answer is -17/36
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