Subtract 8/63 from 7/90
7/90 - 8/63 is -31/630.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 63 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 63 × 10 = 630,
8/63 = 8 × 10/63 × 10 = 80/630 - Subtract the two like fractions:
49/630 - 80/630 = 49 - 80/630 = -31/630
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