Subtract 3/7 from 20/90
20/90 - 3/7 is -13/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 7 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
20/90 = 20 × 7/90 × 7 = 140/630 - Likewise, for the 2nd fraction, since 7 × 90 = 630,
3/7 = 3 × 90/7 × 90 = 270/630 - Subtract the two like fractions:
140/630 - 270/630 = 140 - 270/630 = -130/630 - After reducing the fraction, the answer is -13/63
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