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