Subtract 21/5 from 20/45
1st number: 20/45, 2nd number: 4 1/5
20/45 - 21/5 is -169/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 5 is 45
Next, find the equivalent fraction of both fractional numbers with denominator 45 - For the 1st fraction, since 45 × 1 = 45,
20/45 = 20 × 1/45 × 1 = 20/45 - Likewise, for the 2nd fraction, since 5 × 9 = 45,
21/5 = 21 × 9/5 × 9 = 189/45 - Subtract the two like fractions:
20/45 - 189/45 = 20 - 189/45 = -169/45
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