Subtract 45/4 from 20/21
1st number: 20/21, 2nd number: 11 1/4
20/21 - 45/4 is -865/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 4 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
20/21 = 20 × 4/21 × 4 = 80/84 - Likewise, for the 2nd fraction, since 4 × 21 = 84,
45/4 = 45 × 21/4 × 21 = 945/84 - Subtract the two like fractions:
80/84 - 945/84 = 80 - 945/84 = -865/84
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