Subtract 90/72 from 8/18
1st number: 8/18, 2nd number: 1 18/72
8/18 - 90/72 is -29/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 18 × 4 = 72,
8/18 = 8 × 4/18 × 4 = 32/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
90/72 = 90 × 1/72 × 1 = 90/72 - Subtract the two like fractions:
32/72 - 90/72 = 32 - 90/72 = -58/72 - After reducing the fraction, the answer is -29/36
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