Subtract 5/7 from 20/90
20/90 - 5/7 is -31/63.
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,
5/7 = 5 × 90/7 × 90 = 450/630 - Subtract the two like fractions:
140/630 - 450/630 = 140 - 450/630 = -310/630 - After reducing the fraction, the answer is -31/63
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