Subtract 50/21 from 7/90
1st number: 7/90, 2nd number: 2 8/21
7/90 - 50/21 is -1451/630.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
7/90 = 7 × 7/90 × 7 = 49/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
50/21 = 50 × 30/21 × 30 = 1500/630 - Subtract the two like fractions:
49/630 - 1500/630 = 49 - 1500/630 = -1451/630
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