Subtract 30/21 from 90/18
1st number: 5 0/18, 2nd number: 1 9/21
90/18 - 30/21 is 25/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
90/18 = 90 × 7/18 × 7 = 630/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
30/21 = 30 × 6/21 × 6 = 180/126 - Subtract the two like fractions:
630/126 - 180/126 = 630 - 180/126 = 450/126 - After reducing the fraction, the answer is 25/7
- In mixed form: 34/7
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