Subtract 20/9 from 45/21
1st number: 2 3/21, 2nd number: 2 2/9
45/21 - 20/9 is -5/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
45/21 = 45 × 3/21 × 3 = 135/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
20/9 = 20 × 7/9 × 7 = 140/63 - Subtract the two like fractions:
135/63 - 140/63 = 135 - 140/63 = -5/63
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