Subtract 21/18 from 90/7
1st number: 12 6/7, 2nd number: 1 3/18
90/7 - 21/18 is 491/42.
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,
90/7 = 90 × 18/7 × 18 = 1620/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
21/18 = 21 × 7/18 × 7 = 147/126 - Subtract the two like fractions:
1620/126 - 147/126 = 1620 - 147/126 = 1473/126 - After reducing the fraction, the answer is 491/42
- In mixed form: 1129/42
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