Subtract 7/90 from 30/21
1st number: 1 9/21, 2nd number: 7/90
30/21 - 7/90 is 851/630.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
30/21 = 30 × 30/21 × 30 = 900/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
7/90 = 7 × 7/90 × 7 = 49/630 - Subtract the two like fractions:
900/630 - 49/630 = 900 - 49/630 = 851/630 - In mixed form: 1221/630
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