Subtract 90/18 from 4/7
1st number: 4/7, 2nd number: 5 0/18
4/7 - 90/18 is -31/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 7 × 18 = 126,
4/7 = 4 × 18/7 × 18 = 72/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
90/18 = 90 × 7/18 × 7 = 630/126 - Subtract the two like fractions:
72/126 - 630/126 = 72 - 630/126 = -558/126 - After reducing the fraction, the answer is -31/7
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