Subtract 7/18 from 90/21
1st number: 4 6/21, 2nd number: 7/18
90/21 - 7/18 is 491/126.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
90/21 = 90 × 6/21 × 6 = 540/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
7/18 = 7 × 7/18 × 7 = 49/126 - Subtract the two like fractions:
540/126 - 49/126 = 540 - 49/126 = 491/126 - In mixed form: 3113/126
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