Subtract 21/18 from 20/35
1st number: 20/35, 2nd number: 1 3/18
20/35 - 21/18 is -25/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 18 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 35 × 18 = 630,
20/35 = 20 × 18/35 × 18 = 360/630 - Likewise, for the 2nd fraction, since 18 × 35 = 630,
21/18 = 21 × 35/18 × 35 = 735/630 - Subtract the two like fractions:
360/630 - 735/630 = 360 - 735/630 = -375/630 - After reducing the fraction, the answer is -25/42
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