Subtract 81/70 from 20/90
1st number: 20/90, 2nd number: 1 11/70
20/90 - 81/70 is -589/630.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 70 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 70 × 9 = 630,
81/70 = 81 × 9/70 × 9 = 729/630 - Subtract the two like fractions:
140/630 - 729/630 = 140 - 729/630 = -589/630
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